代码中的错误是什么。？它没有被执行。该怎么办？

问：

我正在使用 kaggle notebook 使用 SQL 清理数据集。 我打算转换表“housing”的“Saledate”列，该表具有时间戳到日期数据类型。 下面是代码

# This Python 3 environment comes with many helpful analytics libraries installed
# It is defined by the kaggle/python Docker image: https://github.com/kaggle/docker-python
# For example, here's several helpful packages to load

import numpy as np # linear algebra
import pandas as pd # data processing, CSV file I/O (e.g. pd.read_csv)

# Input data files are available in the read-only "../input/" directory
# For example, running this (by clicking run or pressing Shift+Enter) will list all files under the input directory

import os
for dirname, _, filenames in os.walk('/kaggle/input'):
    for filename in filenames:
        print(os.path.join(dirname, filename))

# You can write up to 20GB to the current directory (/kaggle/working/) that gets preserved as output when you create a version using "Save & Run All" 
# You can also write temporary files to /kaggle/temp/, but they won't be saved outside of the current session


# loading dataset to dataframe
dataframe=pd.read_excel('/kaggle/input/nashville-housing-data/Nashville Housing Data for Data Cleaning (reuploaded).xlsx')
dataframe

#importing create_engine from sqlalchemy module

from sqlalchemy import create_engine

#creating engine

engine=create_engine('sqlite://', echo=False)

#loading dataframe to the sql table with name "housing"
dataframe.to_sql("housing",con=engine)

sql='''
UPDATE housing
SET Saledate = CONVERT(Date, Saledate);'''

with engine.connect() as connection:
    result = connection.execute(sql)

代码未执行。 这有什么错误？？有人可以帮我吗