@classmethod
	def unpack (cls, data):
		rd = RouteDistinguisher.unpack(data[:8])
		etag = EthernetTag.unpack(data[8:12])
		iplen = ord(data[12])
		if (4*8,16*8) not in iplen:
			raise Exception("IP len is %d, but EVPN route currently support only IPv4" % iplen)
		ip = IP.unpack(data[13:13+iplen/8])
		return cls(rd,etag,ip,data)
dataset/ETHPy150Open Exa-Networks/exabgp/lib/exabgp/bgp/message/update/nlri/evpn/multicast.py/Multicast.unpack/swapped operands of `not in`