-- binary
04 0d # version, type
00 33 # length
12 34 56 78 # xid
00 00 00 64 # buffer_id
00 00 00 04 # in_port
00 18 # actions_len
00 00 00 00 00 00 # pad
00 00 # actions[0].type
00 10 # actions[0].length
00 00 00 02 # actions[0].port
ff ff # actions[0].max_len
00 00 00 00 00 00 # pad
00 18 # actions[1].type
00 08 # actions[1].length
00 00 00 00 # pad
61 62 63 # data
-- python
ofp.message.packet_out(
    xid=0x12345678,
    buffer_id=100,
    in_port=4,
    actions=[
        ofp.action.output(port=2, max_len=0xffff),
        ofp.action.dec_nw_ttl()],
    data="abc")