flask wtforms在提交后保持为空

from flask import Flask, render_template, request
from flask_wtf import FlaskForm
from wtforms import StringField, SubmitField

app = Flask(__name__)
app.config['SECRET_KEY'] = 'your-secret-key'

class MyForm(FlaskForm):
    name = StringField('Name')
    submit = SubmitField('Submit')

@app.route('/', methods=['GET', 'POST'])
def index():
    form = MyForm()
    if form.validate_on_submit():
        # 处理表单提交
        # 重置表单字段的值
        form.reset()
        return 'Form submitted successfully!'
    return render_template('index.html', form=form)

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