def METHOD_NAME(self):
    if self.context.portal_type in ('Collection', 'Feed'):
        self.fields = field.Fields(IFeedSettings).omit('sort_on', 'sort_reverse')
    else:
        self.fields = field.Fields(IFeedSettings)
    self.fields['feed_types'].widgetFactory = SelectFieldWidget
    self.fields['podcast_image'].widgetFactory = ImageRelatedItemFieldWidget
    super(SettingsForm, self).METHOD_NAME()