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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 _notify(self, func, *args, **kw):
 """ Internal helper. Calls the IStreamListener function 'func' with the given args, guarding around errors. """

        for x in self.listeners:
            try:
                getattr(x, func)(*args, **kw)
            except Exception:
                log.err()