def input(self):
        """
        Declare an input.

        This is a decorator for methods.
        """
        def decorator(inputMethod):
            return MethodicalInput(automaton=self._automaton,
                                   method=inputMethod,
                                   symbol=self._symbol)
        return decorator

        Declare an input.

        This is a decorator for methods.
        
stackoverflow/venv/lib/python3.6/site-packages/automat/_methodical.py