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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 data(self):
 """this property just calls ``get_data`` but here you can serilalize your data or render as html these data will be saved to self.cached_content also will be accessable from template """

        if self.is_obsolete():
            self.update_cache(self.get_data())
        return self.cache_data