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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 secure(cls):
 """Uses only authentication mechanisms that are secure for use in non-encrypted sessions. Returns: A new :class:`SASLAuth` object. """

        builtin_mechs = cls._get_builtin_mechanisms()
        secure_mechs = [mech for _, mech in builtin_mechs.items()
                        if not mech.insecure and mech.priority is not None]
        return SASLAuth(secure_mechs)