Returns an object which is generated from a buffer including the
        expression of the wire protocol of the flow stats.

def parser(cls, buf, offset):
        """
        Returns an object which is generated from a buffer including the
        expression of the wire protocol of the flow stats.
        """
        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