old_contents: 
  
  class SceneLoader:
      """Base class for object loaders"""
      def __init__(self, **kwargs):
          pass
  
      def load(self):
          """Loads and returns the scene"""
          raise NotImplemented
  
new_contents: 
  
  class SceneLoader:
      """Base class for object loaders"""
      # File extensions supported by this loader
      file_extensions = []
  
      def __init__(self, file_path, **kwargs):
          self.file_path = file_path
  
      def load(self, scene, file=None):
          """
          Deferred loading of the scene
  
          :param scene: The scene object
          :param file: Resolved path if changed by finder
          """
          raise NotImplemented
  
      @classmethod
      def supports_file(cls, path):
          """Check if the loader has a supported file extension"""
          for ext in cls.file_extensions:
              if path.endswith(ext):
                  return True
  
          return False
  
subject: Make base SceneLoader matter again