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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 connection_made(self, transport):
 """Used to signal `asyncio.Protocol` of a successful connection."""

        self._transport = transport
        self._raw_transport = transport
        if isinstance(transport, asyncio.SubprocessTransport):
            self._transport = transport.get_pipe_transport(0)