docs: def execute(sql, args=None, key='default'):
      """It is used for update, delete records.
  
      :param sql string: the sql stamtement like 'select * from %s'
      :param args  list: Wen set None, will use dbi execute(sql), else
              dbi execute(sql, args), the args keep the original rules, it shuld be tuple or list of list
      :param key: a key for your dabtabase you wanna use
  
      eg::
  
          execute('insert into users values(%s, %s)', [(1L, 'blablabla'), (2L, 'animer')])
          execute('delete from users')
      """
      database = __db[key]
      return database.execute(sql, args)