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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_next_page(self, page_num, page_size):
 """ Retrieve the next page of results. """

        url = self._response_json.get(self.next_page_attr, None)
        if url is None:
            raise StopIteration()
        params, url = self.process_url(page_num, page_size, url)
        response = self.response_handler.api._get(url, raw_response=True, params=params)
        return response.json()