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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 get_random_submission(self, subreddit='all'):
 """Return a random Submission object. :param subreddit: Limit the submission to the specified subreddit(s). Default: all """

        url = self.config['subreddit_random'].format(
            subreddit=six.text_type(subreddit))
        try:
            item = self.request_json(url,
                                     params={'unique': self._unique_count})
            self._unique_count += 1  # Avoid network-level caching
            return objects.Submission.from_json(item)
        except errors.RedirectException as exc:
            self._unique_count += 1
            return self.get_submission(exc.response_url)
        raise errors.ClientException('Expected exception not raised.')