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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 load_template_source(self, *ka):
 """ Backward compatible method for Django < 2.0. """

        template_name = ka[0]
        for origin in self.get_template_sources(template_name):
            try:
                return self.get_contents(origin), origin.name
            except TemplateDoesNotExist:
                pass
        raise TemplateDoesNotExist(template_name)