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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 _purge_consumer_by_tag(self, consumer_tag):
        '''Purge consumer entry from this basic instance

        NOTE: this protected method may be called by derived classes

        :param str consumer_tag:
        '''
        try:
            del self._consumer_cb[consumer_tag]
        except KeyError:
            self.logger.warning(
                'no callback registered for consumer tag " %s "', consumer_tag)
        else:
            self.logger.info('purged consumer with tag " %s "', consumer_tag)