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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_switch_address(addr, interval=None):
 """ Registers a new address to initiate connection to switch. Registers a new IP address and port pair of switch to let ryu.controller.controller.OpenFlowController to try to initiate connection to switch. :param addr: A tuple of (host, port) pair of switch. :param interval: Interval in seconds to try to connect to switch """

    assert len(addr) == 2
    assert ip.valid_ipv4(addr[0]) or ip.valid_ipv6(addr[0])
    ofp_handler = app_manager.lookup_service_brick(ofp_event.NAME)
    _TMP_ADDRESSES[addr] = interval

    def _retry_loop():
        # Delays registration if ofp_handler is not started yet
        while True:
            if ofp_handler.controller is not None:
                for a, i in _TMP_ADDRESSES.items():
                    ofp_handler.controller.spawn_client_loop(a, i)
                    hub.sleep(1)
                break
            hub.sleep(1)

    hub.spawn(_retry_loop)