code: def connect(self):
          
          self.conn = self.db_module.connect(
                  host=self.host, port=int(self.port), user=self.user,
                  passwd=self.passwd, db=self.dbname, charset=self.charset,
                  cursorclass=self.cursorclass)
          self.conn.autocommit(self.autocommit)
          return True
docs: obj.connect() => True or raise Error from MySQLdb.
          You aren't suggested to use this function by your hand,
          because this func may cause Exception.