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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 reducer_output(self, metro, values):
 """ store each record in MongoDB and output tab delimited lines """

        records = []
        # build up list of data for each metro area and submit as one network
        # call instead of individually 
        for value in values:
            total, poi = value
            records.append(dict(
                metro_area=metro,
                poi=poi,
                count=total
            ))
            output = "{0}\t{1}\t{2}"
            output = output.format(metro.encode('utf-8'), total, poi.encode('utf-8'))
            yield None, output
        if self.mongo:
            self.mongo.insert_many(records)