code: def _read_mode_acopt(self, size, kind):
          
          temp = self._read_unpack(size)
          algo = chksum_opt.get(temp)
  
          data = dict(
              kind=kind,
              length=size,
              ac=algo,
          )
  
          return data
docs: Read Alternate Checksum Request option.
  
          Positional arguments:
              size - int, length of option
              kind - int, 14 (Alt-Chksum Request)
  
          Returns:
              * dict -- extracted Alternate Checksum Request (CHKSUM-REQ) option
  
          Structure of TCP CHKSUM-REQ [RFC 1146][RFC 6247]:
              +----------+----------+----------+
              |  Kind=14 | Length=3 |  chksum  |
              +----------+----------+----------+
  
              Octets      Bits        Name                    Description
                0           0     tcp.chksumreq.kind      Kind (14)
                1           8     tcp.chksumreq.length    Length (3)
                2          16     tcp.chksumreq.ac        Checksum Algorithm