-- binary
04 12 # version, type
00 3c # length
12 34 56 78 # xid
ff ff # stats_type
00 00 # flags
00 00 00 00 # pad
00 5c 16 c7 # experimenter
00 00 00 2 # subtype
00 14 # table_id
00 00 # pad
fe dc ba 98 76 54 32 10 ff ee cc bb aa 99 00 00 # checksum
ff ff ff ff ff ff ff ff ff ff ff ff ff ff 00 00 # checksum_mask
-- python
ofp.message.bsn_gentable_entry_desc_stats_request(
    xid=0x12345678,
    table_id=20,
    checksum=     0xFEDCBA9876543210FFEECCBBAA990000,
    checksum_mask=0xFFFFFFFFFFFFFFFFFFFFFFFFFFFF0000)