mathlib3

4c2567ff - chore(group_theory/group_action/group): add `smul_inv` (#7568)

chore(group_theory/group_action/group): add `smul_inv` (#7568) This renames the existing `smul_inv` to `smul_inv'`, which is consistent with the name of the other lemma about `mul_semiring_action`, `smul_mul'`.