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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def refresh(self, ctx: Context_T, *, current_arg: str = '') -> None: """ Refill the session with a new message context. :param ctx: new message context :param current_arg: new command argument as a string """

        self.ctx = ctx
        self.current_arg = current_arg
        self._current_arg_text = None
        self._current_arg_images = None