docs: def automain(module, *, args=(), kwargs=None):
      '''
      This decorator automatically invokes a function if the module is being run
      as the "__main__" module. Optionally, provide args or kwargs with which to
      call the function. If `module` is "__main__", the function is called, and
      the program is `sys.exit`ed with the return value. You can also pass `True`
      to cause the function to be called unconditionally. If the function is not
      called, it is returned unchanged by the decorator.
  
      Usage:
  
      @automain(__name__)  # Pass __name__ to check __name__=="__main__"
      def main():
          ...
  
      If __name__ is "__main__" here, the main function is called, and then
      sys.exit called with the return value.
      '''
  
      # Check that @automain(...) was called, rather than @automain
      if callable(module):
          raise AutomainRequiresModuleError(module)
  
      if module == '__main__' or module is True:
          if kwargs is None:
              kwargs = {}
  
          # Use a function definition instead of a lambda for a neater traceback
          def automain_decorator(main):
              sys.exit(main(*args, **kwargs))
  
          return automain_decorator
      else:
          return lambda main: main