docs: def confirm_register_form_factory(Form, app):
      """Return confirmation for extended registration form."""
      if app.config.get('RECAPTCHA_PUBLIC_KEY') and \
              app.config.get('RECAPTCHA_PRIVATE_KEY'):
          class ConfirmRegisterForm(Form):
              recaptcha = FormField(RegistrationFormRecaptcha, separator='.')
  
          return ConfirmRegisterForm
  
      return Form