Arguments, local variables, and global variables that encode convention in Python

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In python, there is no way to differentiate between arguments, local variables, and global variables. The easy way to do so might be have some coding convention such as

  • Global variables start with _ and capital letter
  • arguments end with with _
_Gvariable = 10
def hello(x_, y_):
   z = x_ + y_

Is this a Pythonian way to go? I mean, is there well established/agreed coding-standards to differentiate them in python?

=== ADDED ===

I just want to discriminate between arguments and local variables. As arguments are given from outside, and more like a ROM in the sense that it is not assumed to be read only. C++ provides the const keyword to prevent the arguments from changing, but not for python. I thought appending _ can be one of a way to mimic this feature in python.


I would do all your python programming according to PEP 8 guidelines. Anyone who has to read your code will thank you for it.

http://www.python.org/dev/peps/pep-0008/

Why is there a need to distinguish between arguments and local variables, since one is merely a subset of the other. You can use locals(), globals(), and vars() to view scope if you are having local-global issues. The inspect module can help with that, too. And if possible, avoid using global variables as much as possible.