def sleepy(reps, snooze):
    t = []
for x in range(reps):
    x = time.time()
time.sleep(snooze)
y = time.time()
global z
z = y - x
t.append(z)
print('difference = ', z * 1000)
print('total:', sum(t) / reps * 1000)
Невозможно вернуть значение из функции