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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 log_stack(self, signal, frame):
 """Signal handler to log the stack trace of the current thread. For use with `set_blocking_signal_threshold`. """

        gen_log.warning('IOLoop blocked for %f seconds in\n%s',
                        self._blocking_signal_threshold,
                        ''.join(traceback.format_stack(frame)))