You use it inside IPython, with a command like: %run -n foo.py You can't set __name__ to arbitrary values. It's either '__main__' like when running a script,

You use it inside IPython, with a command like: %run -n foo.py You can't set __name__ to arbitrary values. It's either '__main__' like when running a script, or (with -n) the module name, like when performing an import.