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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 discard_incoming_messages(self):
 """ Discard all incoming messages for the time of the context manager. """

        # Flush any received message so far.
        self.inbox.clear()

        # This allows nesting of discard_incoming_messages() calls.
        previous = self._discard_incoming_messages
        self._discard_incoming_messages = True

        try:
            yield
        finally:
            self._discard_incoming_messages = previous