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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(self, *args, **kwargs):
 """ Queue a first item to execute, then wait for the queue to be empty before returning. This should be the default way of starting any scraper. """

        if self._source is not None:
            return self._source.run(*args, **kwargs)
        else:
            self.queue(*args, **kwargs)
            return self.wait()