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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_resource(self, relative_url, params=None):
 """Convenience function for retrieving a resource. If resource does not exist, return None. """

        response = self._get(relative_url, params=params, raise_for_status=False)
        if response.status_code == 404:
            return None
        self._raise_for_status(response)
        return response.json()