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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 discrete(self, *args):
 """ Set fields to be discrete. :rtype: DataFrame :Example: """

        new_df = copy_df(self)
        fields = _render_field_set(args)
        self._assert_ml_fields_valid(*fields)
        new_df._perform_operation(op.FieldContinuityOperation(dict((_get_field_name(f), False) for f in fields)))
        return new_df