public final class Q {
  public static final class Stage {
    public static Builder newBuilder() { return new Builder(); }
    public static final class Builder { }
    public Builder toBuilder() { return newBuilder(); }
  }
  public static final class WorkUnit {
    public static Builder newBuilder() { return new Builder(); }
    public static final class Builder { }
    public Builder toBuilder() { return newBuilder(); }
  }
}