old_contents: from wtforms.form import Form
  from wtforms.validators import ValidationError
  
  from .fields import CSRFTokenField
  
  
  class SecureForm(Form):
      """
      Form that enables CSRF processing via subclassing hooks.
      """
      csrf_token = CSRFTokenField()
  
      def __init__(self, formdata=None, obj=None, prefix='', csrf_context=None, **kwargs):
          """
          :param csrf_context: Optional extra data which is passed
                  transparently to your CSRF implementation.
          """
          super(SecureForm, self).__init__(formdata, obj, prefix, **kwargs)
          self.csrf_token.current_token = self.generate_csrf_token(csrf_context)
  
      def generate_csrf_token(self, csrf_context):
          """
          Implementations must override this to provide a method with which one
          can get a CSRF token for this form.
  
          A CSRF token should be a string which can be generated
          deterministically so that on the form POST, the generated string is
          (usually) the same assuming the user is using the site normally.
  
          :param csrf_context: A transparent object which can be used as
                   contextual info for generating the token.
          """
          raise NotImplementedError()
  
      def validate_csrf_token(self, field):
          """
          Override this method to provide custom CSRF validation logic.
  
          The default CSRF validation logic simply checks if the recently
          generated token equals the one we received as formdata.
          """
          if field.current_token != field.data:
              raise ValidationError('Invalid CSRF Token')
  
      @property
      def data(self):
          d = super(SecureForm, self).data
          d.pop('csrf_token')
          return d
  
new_contents: from wtforms.form import Form
  from wtforms.validators import ValidationError
  
  from .fields import CSRFTokenField
  
  
  class SecureForm(Form):
      """
      Form that enables CSRF processing via subclassing hooks.
      """
      csrf_token = CSRFTokenField()
  
      def __init__(self, formdata=None, obj=None, prefix='', csrf_context=None, **kwargs):
          """
          :param csrf_context: 
              Optional extra data which is passed transparently to your 
              CSRF implementation.
          """
          super(SecureForm, self).__init__(formdata, obj, prefix, **kwargs)
          self.csrf_token.current_token = self.generate_csrf_token(csrf_context)
  
      def generate_csrf_token(self, csrf_context):
          """
          Implementations must override this to provide a method with which one
          can get a CSRF token for this form.
  
          A CSRF token should be a string which can be generated
          deterministically so that on the form POST, the generated string is
          (usually) the same assuming the user is using the site normally.
  
          :param csrf_context: 
              A transparent object which can be used as contextual info for
              generating the token.
          """
          raise NotImplementedError()
  
      def validate_csrf_token(self, field):
          """
          Override this method to provide custom CSRF validation logic.
  
          The default CSRF validation logic simply checks if the recently
          generated token equals the one we received as formdata.
          """
          if field.current_token != field.data:
              raise ValidationError(field.gettext(u'Invalid CSRF Token'))
  
      @property
      def data(self):
          d = super(SecureForm, self).data
          d.pop('csrf_token')
          return d
  
subject: Clean up inline documentation, and also use i18n