What is the naming convention in Python for variable and function names?

Question

Coming from a C# background the naming convention for variables and method names are usually either camelCase or PascalCase:

Answer 1

There is a paper about this: http://www.cs.kent.edu/~jmaletic/papers/ICPC2010-CamelCaseUnderScoreClouds.pdf

TL;DR It says that snake_case is more readable than camelCase. That's why modern languages use (or should use) snake wherever they can.