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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 _init_queue():
 """Initialise the Processing Block queue from the database. This method should populate the queue from the current state of the Configuration Database. This needs to be based on the current set of Processing Blocks in the database and consider events on these processing blocks. """

        LOG.info('Initialising Processing Block queue.')
        queue = ProcessingBlockQueue()
        active_pb_ids = ProcessingBlockList().active
        LOG.info('Initialising PC PB queue: %s', active_pb_ids)
        for pb_id in active_pb_ids:
            pb = ProcessingBlock(pb_id)
            queue.put(pb.id, pb.priority, pb.type)
        return queue