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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 clear_database(self):
 """ Removes all geodata stored in database. Useful for development, never use on production. """

        self.logger.info('Removing obsolete geoip from database...')
        IpRange.objects.all().delete()
        City.objects.all().delete()
        Region.objects.all().delete()
        Country.objects.all().delete()