[Bug] Shell completion doesn't work with `python -m module_name ...`

[bryant1410]

🐛 Bug

Description

At least for Bash, Shell completion doesn't work if the program is called like python -m [module_name] .... I see shell completion works if the main command is not Python, or if it's like python [file_path] .... But we can also call it from a Python module (python -m syntax), which in turn runs a __main__.py file from the module.

Expected Behavior

Shell completion to work (e.g., when trying to auto-complete a config group name).