PYW (Python GUI Source File)
The PYW Developer file format
Files with the PYW extension are associated with the programming language Python. They contain code written in Python which displays a GUI (Graphical User Interface). However, even though the code is written in Python, python is not able to run PYW files. They have to be run using pythonw instead.
Technical details of PYW files
PYW files can contain two different kinds of code. One is standard Python code, the other is graphical Python code.