@JohnTESlade的回答更进一步。谷歌的python风格指南有一些非常简洁的建议，

避免使用的名字

除计数器或迭代器外的单字符名称 在任何包/模块名称中使用破折号(-) \ __double_leading_and_trailing_下划线名称(由Python保留)

命名约定

"Internal" means internal to a module or protected or private within a class. Prepending a single underscore (_) has some support for protecting module variables and functions (not included with import * from). Prepending a double underscore (__) to an instance variable or method effectively serves to make the variable or method private to its class (using name mangling). Place related classes and top-level functions together in a module. Unlike Java, there is no need to limit yourself to one class per module. Use CapWords for class names, but lower_with_under.py for module names. Although there are many existing modules named CapWords.py, this is now discouraged because it's confusing when the module happens to be named after a class. ("wait -- did I write import StringIO or from StringIO import StringIO?")

指南源自圭多的建议

通常，要遵循语言标准库中使用的约定。

There is PEP 8, as other answers show, but PEP 8 is only the styleguide for the standard library, and it's only taken as gospel therein. One of the most frequent deviations of PEP 8 for other pieces of code is the variable naming, specifically for methods. There is no single predominate style, although considering the volume of code that uses mixedCase, if one were to make a strict census one would probably end up with a version of PEP 8 with mixedCase. There is little other deviation from PEP 8 that is quite as common.

大多数使用python的人更喜欢下划线，但即使我已经使用python 5年多了，我仍然不喜欢它们。我只是觉得它们很丑，但也许这就是我脑子里的爪哇。

I simply like CamelCase better since it fits better with the way classes are named, It feels more logical to have SomeClass.doSomething() than SomeClass.do_something(). If you look around in the global module index in python, you will find both, which is due to the fact that it's a collection of libraries from various sources that grew overtime and not something that was developed by one company like Sun with strict coding rules. I would say the bottom line is: Use whatever you like better, it's just a question of personal taste.

David Goodger(在这里的“像Pythonista一样编码”中)描述了PEP 8的建议如下:

Joined_lower函数，方法， 属性、变量 joined_lower或ALL_CAPS for 常量 课程用的studlycap 骆驼案只符合 已有的约定

如前所述，PEP 8要求对变量、方法和函数使用lower_case_with_下划线。

我更喜欢使用lower_case_with_下划线的变量和mixedCase的方法和函数，使代码更显式和可读。因此，遵循Python的“显式优于隐式”和“可读性很重要”的禅意。