old_contents: from flask_wtf import FlaskForm
  from wtforms import StringField, PasswordField
  from wtforms.validators import Required, Length, Email
  
  
  class SignupForm(FlaskForm):
      """Render and validate the signup form"""
      email = StringField("Email", validators=[Required(), Email(), Length(1, 32)])
      username = StringField("Username", validators=[Required(), Length(1, 32)])
      password = PasswordField("Password", validators=[Required(), Length(1, 32)])
  
new_contents: from flask_wtf import FlaskForm
  from wtforms import StringField, PasswordField, BooleanField
  from wtforms.validators import DataRequired, Length, Email
  
  
  class SignupForm(FlaskForm):
      """Render and validate the signup form"""
      email = StringField("Email", validators=[DataRequired(), Email(message="Invalid email format"), Length(max=32)])
      username = StringField("Username", validators=[DataRequired(), Length(2, 32)])
      password = PasswordField("Password", validators=[DataRequired(), Length(min=4, max=32)])
  
  
  class LoginForm(FlaskForm):
      """Form to let users login"""
      email = StringField("Username", validators=[DataRequired(), Email(message="Invalid email format"), Length(max=32)])
      password = PasswordField("Password", validators=[DataRequired(), Length(4, 32)])
      remember = BooleanField("Remember Me")
  
subject: Use DataRequired to validate form