old_contents: from wagtail.admin.edit_handlers import BaseChooserPanel
  
  from .widgets import AdminVideoChooser
  
  
  class VideoChooserPanel(BaseChooserPanel):
      model = None
      field_name = None
      _target_model = None
  
      object_type_name = "video"
  
      @classmethod
      def widget_overrides(cls):
          return {cls.field_name: AdminVideoChooser}
  
new_contents: from wagtail.admin.edit_handlers import BaseChooserPanel
  
  from .widgets import AdminVideoChooser
  
  
  class VideoChooserPanel(BaseChooserPanel):
      model = None
      field_name = None
      _target_model = None
  
      object_type_name = "video"
  
      def widget_overrides(self):
          return {self.field_name: AdminVideoChooser}
  
subject: Fix VideoChooserPanel