如何一起验证多个wtform字段以满足某个条件

from wtforms.validators import ValidationError

def validate_fields(form, field):
    if form.field1.data == 'value1' and form.field2.data == 'value2':
        raise ValidationError('条件不满足')

from wtforms import Form, StringField
from wtforms.validators import InputRequired

class MyForm(Form):
    field1 = StringField('字段1', validators=[InputRequired(), validate_fields])
    field2 = StringField('字段2', validators=[InputRequired(), validate_fields])

from flask import Flask, render_template, request
from wtforms import StringField
from wtforms.validators import InputRequired

app = Flask(__name__)

@app.route('/', methods=['GET', 'POST'])
def index():
    form = MyForm(request.form)
    if request.method == 'POST' and form.validate_on_submit():
        # 处理表单提交逻辑
        return '表单验证通过'
    return render_template('index.html', form=form)

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