docs: def _parse_multi_byte(self, s):
          # type: (str) -> int
          """ _parse_multi_byte parses x as a multibyte representation to get the
            int value of this AbstractUVarIntField.
  
          @param str s: the multibyte string to parse.
          @return int: The parsed int value represented by this AbstractUVarIntField.  # noqa: E501
          @raise: AssertionError
          @raise: Scapy_Exception if the input value encodes an integer larger than 1<<64  # noqa: E501
          """
  
          assert(len(s) >= 2)
  
          tmp_len = len(s)
  
          value = 0
          i = 1
          byte = orb(s[i])
          # For CPU sake, stops at an arbitrary large number!
          max_value = 1 << 64
          # As long as the MSG is set, an another byte must be read
          while byte & 0x80:
              value += (byte ^ 0x80) << (7 * (i - 1))
              if value > max_value:
                  raise error.Scapy_Exception(
                      'out-of-bound value: the string encodes a value that is too large (>2^{64}): {}'.format(value)  # noqa: E501
                  )
              i += 1
              assert i < tmp_len, 'EINVAL: x: out-of-bound read: the string ends before the AbstractUVarIntField!'  # noqa: E501
              byte = orb(s[i])
          value += byte << (7 * (i - 1))
          value += self._max_value
  
          assert(value >= 0)
          return value