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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 format(self, response):
 """ Format the data. In derived classes, it is usually better idea to override ``_format_data()`` than this method. :param response: devil's ``Response`` object or the data itself. May also be ``None``. :return: django's ``HttpResponse`` todo: this shouldn't change the given response. only return the formatted response. """


        res = self._prepare_response(response)
        res.content = self._format_data(res.content, self.charset)
        return self._finalize_response(res)