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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 feed_key(self, key_press):
 """ Feed a key press to the CommandLineInterface. """

        assert isinstance(key_press, KeyPress)
        cli = self._active_cli

        # Feed the key and redraw.
        # (When the CLI is in 'done' state, it should return to the event loop
        # as soon as possible. Ignore all key presses beyond this point.)
        if not cli.is_done:
            cli.input_processor.feed(key_press)
            cli.input_processor.process_keys()