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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 _transport_interceptor(self, callback):
 """Takes a callback function and returns a function that takes headers and messages and places them on the main service queue."""


        def add_item_to_queue(header, message):
            queue_item = (
                Priority.TRANSPORT,
                next(
                    self._transport_interceptor_counter
                ),  # insertion sequence to keep messages in order
                (callback, header, message),
            )
            self.__queue.put(
                queue_item
            )  # Block incoming transport until insertion completes

        return add_item_to_queue