python 读取数据库中文内容显示一堆问号

需要在连接数据库时 设置编码格式

def select_db(self,db_name):
     self.conn = MySQLdb.connect( 
         host = self.ip,
         port = self.port,
         user = self.username,
         passwd = self.password,
         charset = 'utf8'
         )
     self.conn.select_db(db_name)