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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 register_pb_devices(num_pbs: int = 100):
 """Register PBs devices. Note(BMo):
 Ideally we do not want to register any devices here. There does not seem to be a way to create a device server with no registered devices in Tango. This is (probably) because Tango devices must have been """

    tango_db = Database()
    LOG.info("Registering PB devices:")
    dev_info = DbDevInfo()
    # pylint: disable=protected-access
    dev_info._class = 'ProcessingBlockDevice'
    dev_info.server = 'processing_block_ds/1'

    for index in range(num_pbs):
        dev_info.name = 'sip_sdp/pb/{:05d}'.format(index)
        LOG.info("\t%s", dev_info.name)
        tango_db.add_device(dev_info)