code: def get(self, key: str, *,
              prompt: Optional[Message_T] = None,
              arg_filters: Optional[List[Filter_T]] = None,
              **kwargs) -> Any:
          
          if key in self.state:
              return self.state[key]
  
          self.current_key = key
          self.current_arg_filters = arg_filters
          self._current_send_kwargs = kwargs
          self.pause(prompt, **kwargs)
docs: Get an argument with a given key.
  
          If the argument does not exist in the current session,
          a pause exception will be raised, and the caller of
          the command will know it should keep the session for
          further interaction with the user.
  
          :param key: argument key
          :param prompt: prompt to ask the user
          :param arg_filters: argument filters for the next user input
          :return: the argument value