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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 retain_error(self, error, frame=None):
 """ Adds details of an error to the report. :param error: The error exception to add to the report. """

        if frame is None:
            stack = traceback.format_exc()
            self.labels.add("@iopipe/error")
        else:
            stack = "\n".join(traceback.format_stack(frame))
            self.labels.add("@iopipe/timeout")
        details = {
            "name": type(error).__name__,
            "message": "{}".format(error),
            "stack": stack,
        }
        self.report["errors"] = details