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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 addfield(self, pkt, s, val):
 """With SSLv2 you will never be able to add a sig_len."""

        v = pkt.tls_session.tls_version
        if v and v < 0x0300:
            return s
        return super(SigLenField, self).addfield(pkt, s, val)