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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 update(uid, post_data):
        '''
        Updat the link.
        '''
        entry = TabLink.update(
            name=post_data['name'],
            link=post_data['link'],
            order=post_data['order'],
            logo=post_data['logo'] if 'logo' in post_data else '',
        ).where(TabLink.uid == uid)
        try:
            entry.execute()
            return True
        except:
            return False