There are many libraries for argument parsing and command line tools; this is mine.

1. Define a controller class

   from scripted import Script
   
   
   script = Script()
   
   
   @script.add_controller
   @script.option('-a', '--option-a', dest='option_a', help='help text')
   @script.option('-b', '--option-b', dest='option_b', help='help text')
   class CommandController(script.Controller):
       """Main parser's help menu created from Controller class docstring.
   
       This is an example controller class used to make complex, deeply
       nested command line tools simple.
       """
   
       @script.argument('-c', '--c3', dest='a3', help='help text')
       @script.argument('c2', dest='c2', help='help text')
       @script.argument('c1', dest='c1', help='help text')
       def command_one(self):
           """Subparser help and desc created from command_one docstring."""
           self.fn.print(f"Called {self.fn.scope} with {self.args}")
           public = self.fn.prompt('username:', mode='stdin')
           private = self.fn.prompt('password:', mode='password')
           self.fn.print(public, private)
   
   
       @script.argument('-d', '--d3', dest='a3', help='help text')
       @script.argument('d2', dest='d2', help='help text')
       @script.argument('d1', dest='d1', help='help text')
       def command_two(self):
           """Sub-parser help menu created from command_two docstring."""
           self.fn.print(f"Called {self.fn.scope} with {self.args}")
   
   
       @script.argument('-e', '--e3', dest='a3', help='help text')
       @script.argument('e2', dest='e2', help='help text')
       @script.argument('e1', dest='e1', help='help text')
       def command_three(self):
           """Subparser help menu created from command_three docstring."""
           self.fn.print(f"Called {self.fn.scope} with {self.args}")
   
   
       def helper(self):
           """Undecorated methods are not introspected."""
           self.fn.print('Helper method')
   
   
   if __name__ == '__main__':
       script.execute()

2. Call the script however python scripts are called.

   python myapp.py -h
   python myapp.py command_one -h