private void computeIsExternal() {
    if (myPosition != null) {
      VirtualFile file = myPosition.getFile();
      PyUtil.runWithProgress(myProject, PyBundle.message("debugger.progress.title.stackframe.processing"), false, true, indicator -> {
        isExternal = ReadAction.compute(() -> {
                                          final Document document = FileDocumentManager.getInstance().getDocument(file);
                                          if (document != null && myProject != null) {
                                            return !ProjectRootManager.getInstance(myProject).getFileIndex().isInContent(file);
                                          }
                                          return true;
                                        });
      });
    }
  }
private void computeIsExternal()