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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 sinks_api(self):
 """Helper for log sink-related API calls. See https://cloud.google.com/logging/docs/reference/v2/rest/v2/projects.sinks """

        if self._sinks_api is None:
            if self._use_grpc:
                self._sinks_api = _gapic.make_sinks_api(self)
            else:
                self._sinks_api = JSONSinksAPI(self)
        return self._sinks_api