simplify `colorsys.rgb_to_hsv`

Feature or enhancement

Proposal:

By inlining some variables, the number of operations performed can be reduced. Example:
with

gc = (maxc-g) / rangec
bc = (maxc-b) / rangec

then

h = bc-gc
h = (maxc-b)/rangec - (maxc-g)/rangec
h = ((maxc-b) - (maxc-g)) / rangec
h = (maxc - b - maxc + g) / rangec
h = (g-b) / rangec

Has this already been discussed elsewhere?

This is a minor feature, which does not need previous discussion elsewhere

Links to previous discussion of this feature:

No response

Linked PRs

• gh-124880

從 colorsys.rgb_to_hsv 入口點開始，並在進行變更前審查連結的 PR gh-124880。當等效計算使用較少的中間操作，同時維持函式行為不變時，工作即完成。