def test_multiply_check(self):
self.assertEqual(multiply(3, 3), 9)
def test_none(self):
with self.assertRaises(ValueError):
multiply(2, None)
def test_zero(self):
with self.assertRaises(ValueError):
multiply(100, 0)
def test_precision(self):
self.assertEqual(multiply(2, .22), .44)
