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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_callbacks(self):
 """Run registered callbacks."""

        for i in range(len(self._callbacks)):
            callback, args = self._callbacks.popleft()
            try:
                callback(*args)
            except Exception:
                self._log.exception('Ignoring exception in callback:')