addresses = set(self.get_interface_addresses(fib, self.pg1))
new_addresses = addresses.difference(self.initial_addresses)
self.assertEqual(len(new_addresses), 2)
addr1 = list(new_addresses)[0]
addr2 = list(new_addresses)[1]
addresses = set(self.get_interface_addresses(fib, self.pg1))
new_addresses = addresses.difference(self.initial_addresses)
self.assertEqual(len(new_addresses), 2)
addr1 = list(new_addresses)[0]
addr2 = list(new_addresses)[1]