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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 get_rating(postid, userid):
        '''
        Get the rating of certain post and user.
        '''
        try:
            recs = TabRating.select().where(
                (TabRating.post_id == postid) & (TabRating.user_id == userid)
            )
        except:
            return False
        if recs.count() > 0:
            return recs.get().rating
        else:
            return False