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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 fetch(self):
 """ Makes a request to combined url with `self._params` as parameters. If the server at combined url responds with Client or Server error, raises an exception. :return: the response from combined url :rtype: requests.models.Response """

        response = self._session.get(self.url, params=self.params)
        response.raise_for_status()
        return response