old_contents: from flask_wtf import Form
  from wtforms import validators
  
  from dmutils.forms import StripWhitespaceStringField
  
  
  class EmailAddressForm(Form):
      email_address = StripWhitespaceStringField('Email address', validators=[
          validators.DataRequired(message="Email can not be empty"),
          validators.Email(message="Please enter a valid email address")
      ])
  
  
  class MoveUserForm(Form):
      user_to_move_email_address = StripWhitespaceStringField('Move an existing user to this supplier', validators=[
          validators.DataRequired(message="Email can not be empty"),
          validators.Email(message="Please enter a valid email address")
      ])
  
  
  class EmailDomainForm(Form):
      new_buyer_domain = StripWhitespaceStringField('Add a buyer email domain', validators=[
          validators.DataRequired(message="The domain field can not be empty.")
      ])
  
new_contents: from flask.ext.wtf import Form
  from wtforms import validators
  
  from dmutils.forms import StripWhitespaceStringField
  
  
  class EmailAddressForm(Form):
      email_address = StripWhitespaceStringField('Email address', validators=[
          validators.DataRequired(message="Email can not be empty"),
          validators.Email(message="Please enter a valid email address")
      ])
  
  
  class MoveUserForm(Form):
      user_to_move_email_address = StripWhitespaceStringField('Move an existing user to this supplier', validators=[
          validators.DataRequired(message="Email can not be empty"),
          validators.Email(message="Please enter a valid email address")
      ])
  
  
  class EmailDomainForm(Form):
      new_buyer_domain = StripWhitespaceStringField('Add a buyer email domain', validators=[
          validators.DataRequired(message="The domain field can not be empty.")
      ])
  
subject: Update import to use new style as per SO answer