__file__ evaluates to the filename, inclusive path, that a
module was loaded from. (Not all modules are required to have a
__file__ attribute, see
PEP 420 for more details).
Simple demonstration
The evaluation of
__file__ is demonstrated with the following simple Python script (
script.py) and
module (
XYZ.py) that the script loads:
import XYZ
print('This script is: ', __file__)
print('XYZ was imported from:', XYZ.__file__)
print('XYZ is implemented in ', __file__)
When executed like so …
P:\ath\to> py example\script.py
… the following is printed:
XYZ is implemented in p:\ath\to\example\XYZ.py
This script is: example\script.py
XYZ was imported from: p:\ath\to\example\XYZ.py