mathlib

35f0f1ba - feat(data/set/basic): Refactor and additions of sep lemmas (#16566)

feat(data/set/basic): Refactor and additions of sep lemmas (#16566) Add and refactor sep lemmas. Co-authored-by: Yaël Dillies <[yael.dillies@gmail.com](mailto:yael.dillies@gmail.com)> Co-authored-by: Wrenna Robson <34025592+linesthatinterlace@users.noreply.github.com>