<s>[INST] What is the naming convention in Python for variable and function names? Coming from a C# background the naming convention for variables and method names are usually either CamelCase or Pascal Case:
// C# example
string thisIsMyVariable = "a"
public void ThisIsMyMethod()

In Python, I have seen the above but I have also seen underscores being used:
# python example
this_is_my_variable = 'a'
def this_is_my_function():

Is there a more preferable, definitive coding style for Python?
 [/INST] See Python PEP 8.

Function names should be lowercase,
  with words separated by underscores as
  necessary to improve readability.
mixedCase is allowed only in contexts
  where that's already the prevailing
  style

Variables...

Use the function naming rules:
  lowercase with words separated by
  underscores as necessary to improve
  readability.

Personally, I deviate from this because I also prefer mixedCase over lower_case for my own projects.
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