LOOPS = 1 << 18 class OldStyleFoo: pass class NewStyleFoo(object): pass def test_simple_loop(): i = 0 while i < LOOPS: i += 1 def test_simple_loop_with_old_style_class_creation(): i = 0 while i < LOOPS: OldStyleFoo() i += 1 def test_simple_loop_with_new_style_class_creation(): i = 0 while i < LOOPS: NewStyleFoo() i += 1 def test_simple_loop_with_new_style_class_new(): i = 0 new = object.__new__ while i < LOOPS: new(NewStyleFoo) i += 1