text: class BtcMessageType(object):
      VERSION = b"version"
      VERACK = b"verack"
      PING = b"ping"
      PONG = b"pong"
      GET_ADDRESS = b"getaddr"
      ADDRESS = b"addr"
      INVENTORY = b"inv"
      GET_DATA = b"getdata"
      NOT_FOUND = b"notfound"
      GET_HEADERS = b"getheaders"
      GET_BLOCKS = b"getblocks"
      TRANSACTIONS = b"tx"
      BLOCK = b"block"
      HEADERS = b"headers"
      REJECT = b"reject"
      SEND_HEADERS = b"sendheaders"
      COMPACT_BLOCK = b"cmpctblock"
      SEND_COMPACT = b"sendcmpct"
      GET_BLOCK_TRANSACTIONS = b"getblocktxn"
      BLOCK_TRANSACTIONS = b"blocktxn"
      FEE_FILTER = b"feefilter"
      XVERSION = b"xversion"
  