How to get an absolute file path in Python

Question

Given a path such as \"mydir/myfile.txt\", how do I find the file\'s absolute path relative to the current working directory in Python? E.g. on Windows, I might

Answer 1

import os
os.path.abspath(os.path.expanduser(os.path.expandvars(PathNameString)))

Note that expanduser is necessary (on Unix) in case the given expression for the file (or directory) name and location may contain a leading ~/(the tilde refers to the user's home directory), and expandvars takes care of any other environment variables (like $HOME).