def test_mean():
    assert mean(4, 5) == 4.5
 def test_mean(self):
     self.assertEqual(mean(4, 5, 6), 4.5)  # wrong
 def test_floats(self):
     assert mean(4.0, 5.0) == 4.5
 def test_basic(self):
     assert mean(4, 5) == 4.5
 def test_none(self):
     with pytest.raises(Exception) as e_info:
         mean()
 def test_one_number(self):
     assert mean(4.0) == 4.0