@Deprecated(forRemoval = true)
  public static @NotNull VirtualFile createChildSequent(Object requestor, @NotNull VirtualFile dir, @NotNull String prefix, @NotNull String extension) throws IOException {
    return dir.createChildData(requestor, getNextAvailableName(dir, prefix, extension));
  }
@Deprecated(forRemoval = true)
  public static @NotNull VirtualFile createChildSequent(Object requestor, @NotNull VirtualFile dir, @NotNull String prefix, @NotNull String extension)