343.lean:24:4-24:24: warning: declaration uses 'sorry'
343.lean:30:0-30:54: error: stuck at solving universe constraint
  max (?u+1) (?u+1) =?= max (?u+1) (?u+1)
while trying to unify
  Catish.Obj Catish.Obj
with
  CatIsh.{max ?u ?u, max (?u + 1) (?u + 1)}
343.lean:30:0-30:54: error: failed to solve universe constraint
  max (?u+1) (?u+1) =?= max (?u+1) (?u+1)
while trying to unify
  Catish.Obj : Type (max ((max (u_1 + 1) (u_2 + 1)) + 1) ((max u_3 u_4) + 1))
with
  CatIsh : Type (max ((max u_4 u_3) + 1) ((max (u_4 + 1) (u_3 + 1)) + 1))