code: def exit_frames(self):
          '''
          Returns a list of frames whose children include a frame outside of the group
          '''
          if self._exit_frames is None:
              exit_frames = []
              for frame in self.frames:
                  if any(c.group != self for c in frame.children):
                      exit_frames.append(frame)
              self._exit_frames = exit_frames
  
          return self._exit_framef exit_frames(self):
          '''
          Returns a list of frames whose children include a frame outside of the group
          '''
          if self._exit_frames is None:
              exit_frames = []
              for frame in self.frames:
                  if any(c.group != self for c in frame.children):
                      exit_frames.append(frame)
              self._exit_frames = exit_frames
  
          return self._exit_frames
docs: Returns a list of frames whose children include a frame outside of the group