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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 _get_choice_attribute(self, value):
 """Get a choice attribute for the given value. Parameters value: ? The value for which we want a choice attribute. Returns ------- An instance of a class based on ``ChoiceAttributeMixin`` for the given value. Raises ------ ValueError If the value is None, as we cannot really subclass NoneType. """


        if value is None:
            raise ValueError('Using `None` in a `Choices` object is not supported. You may '
                             'use an empty string.')

        return create_choice_attribute(self.ChoiceAttributeMixin, value, self)