Before 3.7, dict ordering is documented literally everywhere as "consider it implementation details, use OrderedDict if you need order". From 3.7, it's part of

Before 3.7, dict ordering is documented literally everywhere as "consider it implementation details, use OrderedDict if you need order". From 3.7, it's part of the spec. If you were relying on keys order before, you were not only doing it wrong, but you were doing so despite being told again and again.