<s>[INST] What is __main__.py? What is the __main__.py file for, what sort of code should I put into it, and when should I have one?
 [/INST] Often, a Python program is run by naming a .py file on the command line:
$ python my_program.py

You can also create a directory or zipfile full of code, and include a __main__.py.  Then you can simply name the directory or zipfile on the command line, and it executes the __main__.py automatically:
$ python my_program_dir
$ python my_program.zip
# Or, if the program is accessible as a module
$ python -m my_program

You'll have to decide for yourself whether your application could benefit from being executed like this.
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