code: def _apply_decorators(func, decorators):
      
      decorators = filter(_is_not_none_or_false, reversed(decorators))
  
      for decorator in decorators:
          func = decorator(func)
  
      return func
docs: Apply a list of decorators to a given function.
  
      ``decorators`` may contain items that are ``None`` or ``False`` which will
      be ignored.