def test_02(self):
     numbers = {-13, 2, 10, -7, 100, 55}
     expected = 24.5
     got = lab.arithmetic_mean(numbers)
     self.assertEqual(got, expected)
 def test_03(self):
     numbers = set()
     expected = None
     got = lab.arithmetic_mean(numbers)
     self.assertEqual(got, expected)
 def test_01(self):
     numbers = {1, 2, 6}
     expected = 3
     got = lab.arithmetic_mean(numbers)
     self.assertEqual(got, expected)