code: def parser(cls, buf, offset):
          
          stats = OFPStats()
          reserved, length = struct.unpack_from('!HH', buf, offset)
  
          stats.length = length
  
          # ofp_stats adjustment
          offset += 4
          length -= 4
  
          fields = []
          while length > 0:
              n, value, _, field_len = ofproto.oxs_parse(buf, offset)
              k, uv = ofproto.oxs_to_user(n, value, None)  # No mask
              fields.append((k, uv))
              offset += field_len
              length -= field_len
          stats.fields = fields
          return stats
docs: Returns an object which is generated from a buffer including the
          expression of the wire protocol of the flow stats.