reserve P,Q,X,Y,Z for set, p,x,x9,x1,x2,y,z for object;
reserve D for non empty set;

theorem
  for f being PartFunc of X,X for g being Function of X,X holds f
  tolerates g iff for x being object st x in dom f holds f.x = g.x
proof
  let f be PartFunc of X,X;
  let g be Function of X,X;
  X = {} implies X = {};
  hence thesis by Th74;
end;
