conn = graph.connect_ports(src.output_ports['out'], sink.input_ports['in'])
self.assertEqual(conn.downstream_port.addr, sink.input_ports['in'].addr)
self.assertIs(type(conn), bt2_connection._ConnectionConst)
conn = graph.connect_ports(src.output_ports['out'], sink.input_ports['in'])
self.assertEqual(conn.downstream_port.addr, sink.input_ports['in'].addr)
self.assertIs(type(conn), bt2_connection._ConnectionConst)