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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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