@Contract(value = "null -> false", pure = true)
  public boolean equals(@Nullable Object o) {
    if (this == o) return true;
    if (o == null || getClass() != o.getClass()) return false;

    final DuplicatedPsiTreeElementBase that = (DuplicatedPsiTreeElementBase)o;

    return getValue().equals(that.getValue());
  }
@Contract(value = "null -> false", pure = true)
  public boolean equals(@Nullable Object o)