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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 start(self, plugins):
 """Start listening for msgpack-rpc requests and notifications."""

        self.nvim.run_loop(self._on_request,
                           self._on_notification,
                           lambda: self._load(plugins),
                           err_cb=self._on_async_err)