code: def outpoint(tx_id, index, tree=None):
      '''
      hex_str, int, int -> Outpoint
      accepts block explorer txid string
      '''
      tx_id_le = bytes.fromhex(tx_id)[::-1]
      return tb.make_outpoint(tx_id_le, index, treef outpoint(tx_id, index, tree=None):
      '''
      hex_str, int, int -> Outpoint
      accepts block explorer txid string
      '''
      tx_id_le = bytes.fromhex(tx_id)[::-1]
      return tb.make_outpoint(tx_id_le, index, tree)
docs: hex_str, int, int -> Outpoint
      accepts block explorer txid string