feat(hott/algebra) start to formalize the category of sets (seems to be pretty tough)
feat(hott/algebra) start to formalize the category of sets (seems to be pretty tough)

fgdorais/lean,rlewis1988/lean,fpvandoorn/lean2,johoelzl/lean,dselsam/lean,levnach/lean,levnach/lean,eigengrau/lean,javra/lean,fpvandoorn/lean2,fpvandoorn/lean2,sp3ctum/lean,soonhokong/lean,avigad/lean,leanprover/lean,c-cube/lean,leodemoura/lean,fpvandoorn/lean,UlrikBuchholtz/lean,avigad/lean,avigad/lean,fgdorais/lean,leanprover/lean,eigengrau/lean,eigengrau/lean,avigad/lean,eigengrau/lean,htzh/lean,fgdorais/lean,fgdorais/lean,fpvandoorn/lean,sp3ctum/lean,leodemoura/lean,UlrikBuchholtz/lean,leanprover/lean,soonhokong/lean-osx,htzh/lean,soonhokong/lean-windows,leanprover-community/lean,Kha/lean,fpvandoorn/lean,Kha/lean,dselsam/lean,fpvandoorn/lean,johoelzl/lean,c-cube/lean,fpvandoorn/lean2,leanprover/lean,Kha/lean,leanprover-community/lean,digama0/lean,digama0/lean,avigad/lean,leanprover-community/lean,leanprover-community/lean,javra/lean,dselsam/lean,johoelzl/lean,levnach/lean,rlewis1988/lean,UlrikBuchholtz/lean,leodemoura/lean,soonhokong/lean-osx,rlewis1988/lean,dselsam/lean,johoelzl/lean,htzh/lean,soonhokong/lean,dselsam/lean,digama0/lean,c-cube/lean,soonhokong/lean-osx,sp3ctum/lean,leodemoura/lean,johoelzl/lean,soonhokong/lean-windows,digama0/lean,leodemoura/lean,soonhokong/lean-windows,fpvandoorn/lean,c-cube/lean,javra/lean,soonhokong/lean,fgdorais/lean,digama0/lean,leanprover-community/lean,fgdorais/lean,soonhokong/lean-osx,soonhokong/lean-osx,rlewis1988/lean,soonhokong/lean,Kha/lean,UlrikBuchholtz/lean,leodemoura/lean,soonhokong/lean-windows,sp3ctum/lean,UlrikBuchholtz/lean,fpvandoorn/lean,eigengrau/lean,sp3ctum/lean,leanprover/lean,c-cube/lean,javra/lean,johoelzl/lean,soonhokong/lean-windows,dselsam/lean,rlewis1988/lean,avigad/lean,leanprover/lean,rlewis1988/lean,fpvandoorn/lean2,digama0/lean,javra/lean,Kha/lean,Kha/lean,htzh/lean,levnach/lean,soonhokong/lean,leanprover-community/lean,levnach/lean,htzh/lean