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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 run_callback(self):
 """Calls the callback_func, passing in the two positional arguments, conditionally waiting if the callback function hasn't been set yet. Meant to be run in a threadpool owned by the FutureCollection. Returns: None """


        if self._callback_func is not None:
            try:
                self._callback_func(self._request, self._result)
            except Exception:  # pylint: disable=broad-except
                LOGGER.exception('An unhandled error occurred while running '
                                 'future callback')