出品 | python数据科学
初识Python语言，觉得python满足了我上学时候对编程语言的所有要求。python语言的高效编程技巧让我们这些大学曾经苦逼学了四年c或者c++的人，兴奋的不行不行的，终于解脱了。高级语言，如果做不到这样，还扯啥高级呢？
01 交换变量
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;"><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>>a=<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>>b=<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">6</span></span></p>这个情况如果要交换变量在c++中，肯定需要一个空变量。但是python不需要，只需一行，大家看清楚了
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;"><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>>a,b=b,a<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>>print(a)>>><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">6</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>>ptint(b)>>><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">5</span></span></p>02 字典推导(Dictionary comprehensions)和集合推导(Set comprehensions)
大多数的Python程序员都知道且使用过列表推导(list comprehensions)。如果你对list comprehensions概念不是很熟悉——一个list comprehension就是一个更简短、简洁的创建一个list的方法。
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;"><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> some_list = [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">5</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> another_list = [ x + <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span> for x in some_list ]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> another_list<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />[<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">5</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">6</span>]</span></p>自从python 3.1 起，我们可以用同样的语法来创建集合和字典表：
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;">>>> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(128, 128, 128);"># Set Comprehensions</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />>>> some_list = [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">5</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">5</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">8</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />>>> even_set = { x <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">for</span> x <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">in</span> some_list <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">if</span> x % <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span> == <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">0</span> }<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />>>> even_set<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />set([<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">8</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>])<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />>>> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(128, 128, 128);"># Dict Comprehensions</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />>>> d = { x: x % <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span> == <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">0</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">for</span> x <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">in</span> range(<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">11</span>) }<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />>>> d<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />{<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">False</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">True</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">False</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">True</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">5</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">False</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">6</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">True</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">7</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">False</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">8</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">True</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">9</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">False</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">10</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">True</span>}</span></p>在第一个例子里，我们以some_list为基础，创建了一个具有不重复元素的集合，而且集合里只包含偶数。而在字典表的例子里，我们创建了一个key是不重复的1到10之间的整数，value是布尔型，用来指示key是否是偶数。
这里另外一个值得注意的事情是集合的字面量表示法。我们可以简单的用这种方法创建一个集合：
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;"><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> my_set = {<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>}<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> my_set<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />set([<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>])<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /></span></p>而不需要使用内置函数set()。
03 计数时使用Counter计数对象。
这听起来显而易见，但经常被人忘记。对于大多数程序员来说，数一个东西是一项很常见的任务，而且在大多数情况下并不是很有挑战性的事情——这里有几种方法能更简单的完成这种任务。
Python的collections类库里有个内置的dict类的子类，是专门来干这种事情的：
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;"><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> from collections import Counter<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> c = Counter(<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> hello world </span>)<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> c<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />Counter({<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> l </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> o </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> e </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> d </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> h </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> r </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> w </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>})<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> c.most_common(<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>)<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />[(<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> l </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>), (<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> o </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>)]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /></span></p>04 漂亮的打印出JSON
JSON是一种非常好的数据序列化的形式，被如今的各种API和web service大量的使用。使用python内置的json处理，可以使JSON串具有一定的可读性，但当遇到大型数据时，它表现成一个很长的、连续的一行时，人的肉眼就很难观看了。
为了能让JSON数据表现的更友好，我们可以使用indent参数来输出漂亮的JSON。当在控制台交互式编程或做日志时，这尤其有用：
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;"><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> import json<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> print(json.dumps(data)) <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(128, 128, 128);"># No indention</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />{<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"status"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"OK"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"count"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"results"</span>: [{<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"age"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">27</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"name"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Oz"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"lactose_intolerant"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">true</span>}, {<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"age"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">29</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"name"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Joe"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"lactose_intolerant"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">false</span>}]}<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> print(json.dumps(data, indent=<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>)) <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(128, 128, 128);"># With indention</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />{<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"status"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"OK"</span>,<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"count"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>,<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"results"</span>: [<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> {<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"age"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">27</span>,<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"name"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Oz"</span>,<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"lactose_intolerant"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">true</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> },<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> {<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"age"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">29</span>,<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"name"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Joe"</span>,<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"lactose_intolerant"</span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">false</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> }<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> ]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />}</span></p>同样，使用内置的pprint模块，也可以让其它任何东西打印输出的更漂亮。
05 解决FizzBuzz
前段时间Jeff Atwood 推广了一个简单的编程练习叫FizzBuzz，问题引用如下：
写一个程序，打印数字1到100，3的倍数打印“Fizz”来替换这个数，5的倍数打印“Buzz”，对于既是3的倍数又是5的倍数的数字打印“FizzBuzz”。
这里就是一个简短的，有意思的方法解决这个问题：
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;"><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">for</span> x <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">in</span> range(<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">101</span>):<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">print</span><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"fizz"</span>[x%<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>*<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">len</span>(<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> fizz </span>)::]+<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"buzz"</span>[x%<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">5</span>*<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">len</span>(<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> buzz </span>)::] <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">or</span> x</span></p>06 if 语句在行内
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;"><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">print</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Hello"</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">if</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">True</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">else</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"World"</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />>>> Hello</span></p>07 连接
下面的最后一种方式在绑定两个不同类型的对象时显得很cool。
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;">nfc = [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Packers"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"49ers"</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />afc = [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Ravens"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Patriots"</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />print nfc + afc<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Packers </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> 49ers </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Ravens </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Patriots </span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />print str(<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>) + <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">" world"</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span> world<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />print <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">`1`</span> + <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">" world"</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span> world<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />print <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"world"</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span> world<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />print nfc, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Packers </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> 49ers </span>] <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span></span></p>08 数值比较
这是我见过诸多语言中很少有的如此棒的简便法
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;">x = <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">if</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span> > x > <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>:<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> print x<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">if</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span> < x > <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">0</span>:<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> print x<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span></span></p>09 同时迭代两个列表
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;">nfc = [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Packers"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"49ers"</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />afc = [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Ravens"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Patriots"</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">for</span> teama, teamb <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">in</span> zip(nfc, afc):<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> print teama + <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">" vs. "</span> + teamb<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> Packers vs. Ravens<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">49</span>ers vs. Patriots</span></p>10 带索引的列表迭代
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;">teams = [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Packers"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"49ers"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Ravens"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Patriots"</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">for</span> index, team <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">in</span> enumerate(teams):<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> print index, team<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">0</span> Packers<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">49</span>ers<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span> Ravens<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span> Patriots</span></p>11 列表推导式
已知一个列表，我们可以刷选出偶数列表方法：
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;">numbers = [1,2,3,4,5,6]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />even = []<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />for number in numbers:<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> if number%2 == 0:<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> even.append(number)</span></p>转变成如下：
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;"><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(165, 218, 45);">numbers</span> = [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">5</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">6</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(165, 218, 45);">even</span> = [number for number in numbers if number%<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span> == <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">0</span>]</span></p>12 字典推导
和列表推导类似，字典可以做同样的工作：
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;">teams = [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Packers"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"49ers"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Ravens"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Patriots"</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />print {key: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">value</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">for</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">value</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">key <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;box-sizing: border-box !important;word-wrap: inherit !important;word-break: inherit !important;">in</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(165, 218, 45);box-sizing: border-box !important;word-wrap: inherit !important;word-break: inherit !important;">enumerate</span>(<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(255, 152, 35);box-sizing: border-box !important;word-wrap: inherit !important;word-break: inherit !important;">teams</span>)}<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />>>> </span>{<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> 49ers </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Ravens </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Patriots </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Packers </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">0</span>}</span></p>13 初始化列表的值
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;">items = [0]*3<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />print items<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />>>> [0,0,0]</span></p>14 列表转换为字符串
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;">teams = [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Packers"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"49ers"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Ravens"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Patriots"</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />print <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">", "</span>.join(teams)<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Packers, 49ers, Ravens, Patriots </span></span></p>15 从字典中获取元素
我承认try/except代码并不雅致，不过这里有一种简单方法，尝试在字典中找key，如果没有找到对应的alue将用第二个参数设为其变量值。
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;">data = {<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> user </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> name </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Max </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> three </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>}<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">try</span>:<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> is_admin = data[<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> admin </span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">except</span> KeyError:<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> is_admin = <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">False</span></span></p>替换成这样
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;"><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(165, 218, 45);">data</span> = {<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> user </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> name </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Max </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> three </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>}<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(165, 218, 45);">is_admin</span> = data.get(<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> admin </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">False</span>)</span></p>16 获取列表的子集
有时，你只需要列表中的部分元素，这里是一些获取列表子集的方法。
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;">x = [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">5</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">6</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(128, 128, 128);">#前3个</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />print x[<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">:3</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(128, 128, 128);">#中间4个</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />print x[<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1:5</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">5</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(128, 128, 128);">#最后3个</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />print x[<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3:</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">5</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">6</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(128, 128, 128);">#奇数项</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />print x[<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">::2</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">3</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">5</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(128, 128, 128);">#偶数项</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />print x[<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1::2</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">4</span>,<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">6</span>]</span></p>除了python内置的数据类型外，在collection模块同样还包括一些特别的用例，在有些场合Counter非常实用。如果你参加过在这一年的Facebook HackerCup，你甚至也能找到他的实用之处。
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;"><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">from</span> collections <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">import</span> Counter<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">print</span> Counter(<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"hello"</span>)<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />>>> Counter({<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> l </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> h </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> e </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> o </span>: <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">1</span>})</span></p>17 迭代工具
和collections库一样，还有一个库叫itertools，对某些问题真能高效地解决。其中一个用例是查找所有组合，他能告诉你在一个组中元素的所有不能的组合方式
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;">from itertools import combinations<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />teams = [<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Packers"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"49ers"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Ravens"</span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Patriots"</span>]<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">for</span> game <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">in</span> combinations(teams, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(174, 135, 250);">2</span>):<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> print game<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> (<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Packers </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> 49ers </span>)<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> (<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Packers </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Ravens </span>)<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> (<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Packers </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Patriots </span>)<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> (<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> 49ers </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Ravens </span>)<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> (<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> 49ers </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Patriots </span>)<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(91, 218, 237);">>></span>> (<span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Ravens </span>, <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);"> Patriots </span>)</span></p>18 False == True
比起实用技术来说这是一个很有趣的事，在python中，True和False是全局变量，因此：
<p style="padding: 0.5em;max-width: 100%;min-height: 1em;font-size: 14px;letter-spacing: 0px;font-family: Consolas, Inconsolata, Courier, monospace;border-radius: 0px;color: rgb(169, 183, 198);background: rgb(40, 43, 46);margin-left: 16px;margin-right: 16px;margin-bottom: 20px;line-height: 1.75em;box-sizing: border-box !important;word-wrap: normal !important;word-break: normal !important;overflow: auto !important;"><span style="max-width: 100%;font-size: 15px;box-sizing: border-box !important;word-wrap: break-word !important;"><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">False</span> = <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">True</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">if</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">False</span>:<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">print</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"Hello"</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /><span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">else</span>:<br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" /> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(248, 35, 117);">print</span> <span class="" style="font-size: 15px;max-width: 100%;line-height: inherit;color: rgb(238, 220, 112);">"World"</span><br style="max-width: 100%;box-sizing: border-box !important;word-wrap: break-word !important;" />>>> Hello</span></p>
— 完 —
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