code: def pack_value(self, val):
          
          if isinstance(val, bytes):
              val = list(iterbytes(val))
  
          slen = len(val)
  
          if self.pad:
              pad = b'\0\0' * (slen % 2)
          else:
              pad = b''
  
          return struct.pack('>' + 'H' * slen, *val) + pad, slen, None
docs: Convert 8-byte string into 16-byte list