谁能告诉我为什么我在烧瓶中收到“ NameError：名称'validators'未定义”吗？因为我是烧瓶新手

Question

我在烧瓶中使用Wt表单，我已经安装了wtf模块并使用它来创建表单，但是当我尝试运行该应用程序时，这表明即使我已正确导入它也未定义Validator。 请检查并更正我的代码片段在做什么。 谢谢

我已经在网上检查了多篇文章，但没有解决我的问题

from flask_wtf import FlaskForm
from wtforms import StringField,PasswordField,SubmitField,BooleanField
from wtforms.validators import DataRequired, Length, Email, EqualTo

class RegistrationForm(FlaskForm):
username = StringField('Username', validators[DataRequired(),Length(min=2, max=20)])
email = StringField('Email', validators[DataRequired(), Email()])
password = PasswordField('Password', validators[DataRequired()])
confirm_password = PasswordField('Confirm Password', validators[DataRequired(), EqualTo('password')])
submit =  SubmitField('Sign Up')

class LoginForm(FlaskForm):
email = StringField('Email', validators[DataRequired(), Email()])
password = PasswordField('Password', validators[DataRequired()])
remember = BooleanField('Remember Me')
submit =  SubmitField('Login')

回溯：

Traceback (most recent call last):
File "app.py", line 2, in <module>
from forms import RegistrationForm, LoginForm
File "/Users/bennykhatri/Practice/Flask/Corey/forms.py", line 5, in    <module>
class RegistrationForm(FlaskForm):
File "/Users/bennykhatri/Practice/Flask/Corey/forms.py", line 6, in  RegistrationForm
username = StringField('Username', validators[DataRequired(),  Length(min=2, max=20)])
NameError: name 'validators' is not defined

Answer 1

不，您还没有完成

import validators

这样做的时候

from validators import x, y, z

那么实际上只导入x，y和z。