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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_last(postid):
        '''
        Get the last wiki in history.
        '''
        recs = TabWikiHist.select().where(
            TabWikiHist.wiki_id == postid
        ).order_by(TabWikiHist.time_update.desc())

        return None if recs.count() == 0 else recs.get()