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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_stats(self):
 """Print statistics into log."""

    logging.info('Validation statistics: ')
    for k, v in iteritems(self.stats):
      logging.info('%s - %d valid out of %d total submissions',
                   k, v[0], v[0] + v[1])