验证表单后，Flask WTForm返回上部index.html，但表单是底部索引

from flask import Flask, render_template, redirect, url_for
from flask_wtf import FlaskForm
from wtforms import StringField, SubmitField
from wtforms.validators import DataRequired

app = Flask(__name__)
app.config['SECRET_KEY'] = 'your_secret_key'

class MyForm(FlaskForm):
    name = StringField('Name', validators=[DataRequired()])
    submit = SubmitField('Submit')

@app.route('/', methods=['GET', 'POST'])
def index():
    form = MyForm()
    if form.validate_on_submit():
        # 执行表单验证成功后的逻辑操作

        # 重定向到上部的index.html页面
        return redirect(url_for('index', _anchor='top'))

    return render_template('index.html', form=form)

if __name__ == '__main__':
    app.run()