def test_sharpen_pencil_decrease_length_by_one(self):
w = Write()
w.write_on_paper('abcdef')
self.assertEqual(w.pencil.pointDurability, 39994)
w.sharpen_pencil()
self.assertEqual(w.pencil.pointDurability, 40000)
self.assertEqual(w.pencil.pencilLength, 3)
