
theorem Th21:
  for X,Y,Z being non empty TopSpace st Y,Z are_homeomorphic holds
  oContMaps(X, Y), oContMaps(X, Z) are_isomorphic
proof
  let X,Y,Z be non empty TopSpace;
  given f being Function of Y,Z such that
A1: f is being_homeomorphism;
  reconsider f as continuous Function of Y,Z by A1,TOPS_2:def 5;
  take oContMaps(X, f);
  thus thesis by A1,Th20;
end;
