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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 closed(self, error=None):
 """ Notify the application that the connection has been closed. :param error: The exception which has caused the connection to be closed. If the connection has been closed due to an EOF, pass ``None``. """


        if self._application:
            try:
                self._application.closed(error)
            except Exception:
                # Ignore exceptions from the notification
                pass