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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 _TLS_Ext_CertTypeDispatcher(m, *args, **kargs):
 """ We need to select the correct one on dissection. We use the length for that, as 1 for client version would emply an empty list. """

    tmp_len = struct.unpack("!H", m[2:4])[0]
    if tmp_len == 1:
        cls = TLS_Ext_ServerCertType
    else:
        cls = TLS_Ext_ClientCertType
    return cls(m, *args, **kargs)