先展示问题

没有刷新出数据,网页也没有报错(那个错误不影响)
该页面的源码
show_user.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>数据库</title>
<style>
.t1{
width: 30px;
height: 30px;
margin: 0 auto;
border: 1px black solid;
}
</style>
<!-- <link rel="stylesheet" href="C:\Users\范先生\Desktop\html web\bootstrap-3.4.1-dist\css\bootstrap.css">-->
</head>
<body>
<h1>用户列表</h1>
<table class="t1">
<thead>
<tr>
<td>ID</td>
<td>姓名</td>
<td>密码</td>
<td>手机号</td>
</tr>
</thead>
<tbody>
<tr>
<td>1</td>
<td>XXX</td>
<td>12312313</td>
<td>333333333333</td>
</tr>
{% for item in data %}
<tr>
<td>{{item.id}}</td>
<td>{{item.username}}</td>
<td>{{item.password}}</td>
<td>{{item.mobile}}</td>
</tr>
{% endfor %}
</tbody>
</table>
<!-- <script src="C:\Users\范先生\Desktop\html web\bootstrap-3.4.1-dist\js\jquery-3.7.1.js"></script>-->
<!-- <script src="C:\Users\范先生\Desktop\html web\bootstrap-3.4.1-dist\js\bootstrap.js"></script>-->
</body>
</html>
数据库的数据

主程序代码(这个应该没有问题)
main.py
from flask import app,Flask,render_template,redirect,request
import pymysql
app=Flask(__name__)
@app.route('/add/user',methods=['GET','POST'])
def add_user():
if request.method == 'GET':
return render_template('add_user.html')
username = request.form.get('user')
password = request.form.get('pwd')
mobile = request.form.get('mobile')
conn=pymysql.connect(host='localhost',user='root',password='123',charset='utf8',db='unicom')
cursor=conn.cursor()
sql="insert into admin(username,password,mobile) values(%s,%s,%s)"
cursor.execute(sql,(username,password,mobile))
conn.commit()
cursor.close()
conn.close()
return '添加成功'
# 展示数据库的数据
@app.route('/show/user')
def show_user():
conn=pymysql.connect(host='localhost',user='root',password='123',charset='utf8',db='unicom')
cursor=conn.cursor()
sql="select * from admin"
cursor.execute(sql)
# conn.commit()
data=cursor.fetchall()
for row in data:
print(row)
cursor.close()
conn.close()
return render_template('show_user.html',data=data)
# print(data)
if __name__ == '__main__':
app.run()
添加成员信息的界面(这个也没有问题)
add_user.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h1>添加用户</h1>
<form method="post" action="/add/user">
<input type="text" name="user" placeholder="请输入用户名">
<input type="text" name="pwd" placeholder="请输入密码">
<input type="text" name="mobile" placeholder="请输入手机号">
<input type="submit" value="提 交">
</form>
</body>
</html>
该程序实现的功能就是动态的向数据库中添加成员信息并展示在前端