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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_transport(self):
 """If a transport object has been defined then connect it now."""

        if self.transport:
            if self.transport.connect():
                self.log.debug("Service successfully connected to transport layer")
            else:
                raise RuntimeError("Service could not connect to transport layer")
            # direct all transport callbacks into the main queue
            self._transport_interceptor_counter = itertools.count()
            self.transport.subscription_callback_set_intercept(
                self._transport_interceptor
            )
        else:
            self.log.debug("No transport layer defined for service. Skipping.")