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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 choices(self):
 """ Returns the filter list as a tuple. Useful for model choices. """

        choice_list = getattr(
            settings, 'MARKUP_CHOICES', DEFAULT_MARKUP_CHOICES
        )
        return [(f, self._get_filter_title(f)) for f in choice_list]