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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 query_count():
        '''
        The count of post2tag.
        '''
        recs = TabPost2Tag.select(
            TabPost2Tag.tag_id,
            peewee.fn.COUNT(TabPost2Tag.tag_id).alias('num')
        ).group_by(
            TabPost2Tag.tag_id
        )
        return recs