const or #define coming from C

[SamHobbs]

Yes
Though, truly I cannot speak for the guidance committees. Suggest a PEP that adds constants and see what the reaction is.

Sounds good.

The following is not intended to be a complaint or criticism. In many languages, such as C and C++, enhancement requests must be specific and complete and with strong familiarity with the language. If Python does not have such rigorous requirements then it is worth pursuing by someone interested in doing that. I am sure however that it cannot be a casual effort.

[jefsummers]

Right. It is not trivial, but there is a mechanism. Start by reading PEP 1. This explains what PEPs are, and part way down you get the section "Start with an idea for Python". There are then guides for submission. It does require a GitHub account and the process creates a fork, so you should familiarize yourself with that if you aren't already.

Then it may be a good idea to look at some PEP submissions. Linking to one that Guido submitted and self rejected! Yet I hear something similar is coming in a version soon. https://www.python.org/dev/peps/pep-3103/