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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 client_connected( self, reader: asyncio.StreamReader, writer: asyncio.StreamWriter ) -> None: """ Callback when the TCP connection is established. Record references to the stream reader and the stream writer to avoid using private attributes ``_stream_reader`` and ``_stream_writer`` of :class:`~asyncio.StreamReaderProtocol`. """

        self.reader = reader
        self.writer = writer