def test_calculator(self):
self.assertEqual(a1.calculator(3, 3, 'add'), 6)
self.assertEqual(a1.calculator(3, 3, 'subtract'), 0)
self.assertEqual(a1.calculator(3, 3, 'multiply'), 9)
self.assertEqual(a1.calculator(3, 3, 'divide'), 1)
self.assertEqual(a1.calculator(2, 6, 'add'), 8)
self.assertEqual(a1.calculator(2, 6, 'subtract'), -4)
self.assertEqual(a1.calculator(2, 6, 'multiply'), 12)
self.assertEqual(a1.calculator(2, 6, 'divide'), 1 / 3)
self.assertEqual(a1.calculator(-3, 4, 'add'), 1)
self.assertEqual(a1.calculator(-3, 4, 'subtract'), -7)
self.assertEqual(a1.calculator(-3, 4, 'multiply'), -12)
self.assertEqual(a1.calculator(-3, 4, 'divide'), -0.75)
