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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 _on_connection_open(self, connection):
 """ Callback invoked when the connection is successfully established. Args: connection (pika.connection.SelectConnection):
 The newly-estabilished connection. """

        _log.info("Successfully opened connection to %s", connection.params.host)
        self._channel = connection.channel(on_open_callback=self._on_channel_open)