code: def update_cnt(uid, post_data):
          '''
          update content.
          '''
  
          entry = TabPost.update(
              cnt_html=tools.markdown2html(post_data['cnt_md']),
              user_name=post_data['user_name'],
              cnt_md=tornado.escape.xhtml_escape(post_data['cnt_md'].strip()),
              time_update=tools.timestamp()
          ).where(TabPost.uid == uid)
          entry.execute(f update_cnt(uid, post_data):
          '''
          update content.
          '''
  
          entry = TabPost.update(
              cnt_html=tools.markdown2html(post_data['cnt_md']),
              user_name=post_data['user_name'],
              cnt_md=tornado.escape.xhtml_escape(post_data['cnt_md'].strip()),
              time_update=tools.timestamp()
          ).where(TabPost.uid == uid)
          entry.execute()
docs: update content.