无法关闭与python的mysql连接

我认为下面的代码在向数据库插入新行后会自动关闭mysql连接，但当我检查连接数时，它看起来并没有关闭。不确定代码出了什么问题

class dbq:

    def __init__(self):

        self._conn = mysql.connector.connect(user='XYZ', password='ZYX',
                                            host='000.111.222.333', database='users')

        self._cursor = self._conn.cursor()

    def closeConn(self):
        self._cursor.close()
        self._conn.close()

    def db_query(self, sql):
        self._cursor.execute(sql)
        rows = self._cursor.fetchall()

        df = DataFrame(rows, columns=self._cursor.column_names)
        return df

    def insert(self, sql, args):
        try:
            self._cursor.execute(sql, args)
            ''' printint is annoying
            if self._cursor.lastrowid:
                print('last insert id', self._cursor.lastrowid)
            else:
                print('last insert id not found')
            '''
            self._conn.commit()
        except Error as error:
            print(error)
        finally:
            self._cursor.close()
            self._conn.close()

def db_insert_master_text(phone, comments):
    sql = "INSERT INTO user_master_text_base(phone, comments, timestamp) VALUES(%s,%s,%s)"
    args = (phone, comments, datetime.datetime.now())
    db = dbq()
    db.insert(sql, args)

当我需要插入新行时，我只需调用：

db_insert_master_text('13473639718', 'Hi')

---

尽管我在定义insert（）时使用了.close（），但调用函数后的连接数始终在增加函数

当错误发生时，您可能也应该关闭它？如何自动关闭它？建议使用

和
python语法，并使用
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