@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

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。

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.

参见Python PEP 8:函数和变量名:

函数名应该是小写的，单词之间用下划线分隔，以提高可读性。 变量名遵循与函数名相同的约定。 mixedCase只允许在已经是流行风格的上下文中使用(例如threading.py)，以保持向后兼容性。

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

有一篇关于这方面的论文:http://www.cs.kent.edu/~jmaletic/papers/ICPC2010-CamelCaseUnderScoreClouds.pdf

它说snake_case比camelCase可读性更好。这就是为什么现代语言在任何可能的地方都使用(或应该使用)蛇。