-- binary
01 0d # version/type
00 23 # length
12 34 56 78 # xid
ab cd ef 01 # buffer_id
ff fe # in_port
00 10 # actions_len
00 00 # actions[0].type
00 08 # actions[0].len
00 01 # actions[0].port
00 00 # actions[0].max_len
00 00 # actions[1].type
00 08 # actions[1].len
00 02 # actions[1].port
00 00 # actions[1].max_len
61 62 63 # data
-- python
ofp.message.packet_out(
    xid=0x12345678,
    buffer_id=0xabcdef01,
    in_port=ofp.OFPP_LOCAL,
    actions=[
        ofp.action.output(port=1),
        ofp.action.output(port=2)],
    data='abc')