Use interned versions of string constants if they're already present

Feature or enhancement

Proposal:

For now intern_constants function in Objects/codeobject.c uses should_intern_string to check if that string should be interned. And do nothing if should_intern_string returned 0. Maybe it'll be better to check if this string already have interned variant and use it if present? Because there's no need to keep equal strings in memory. The small downside is some time needed for this checking.

Has this already been discussed elsewhere?

No response given

Links to previous discussion of this feature:

No response

Linked PRs

• gh-140688

从 Objects/codeobject.c 中的 intern_constants 开始，追踪 should_intern_string 当前如何确定字符串是否会被 intern。在开始之前查看链接的 PR gh-140688，并在能够复用现有的 intern 等价字符串且不再保留重复的相同字符串时，认为工作已完成。