def test_big():
num_list = [1000000000]
observed = calc_mean(num_list)
expected = 1000000000
assert observed == expected
def test_int():
num_list = [1, 2, 3, 4, 5]
observed = calc_mean(num_list)
expected = 3
assert observed == expected
def test_double():
num_list = [1, 2, 3, 4]
observed = calc_mean(num_list)
expected = 2.5
assert observed == expected