python random.randint() did not return any value

I need to append random hours to date field. For this I used following code:

datetime.utcnow().date() + relativedelta(hours=random.randint(0,23))

This returned response:

datetime.date(2018, 7, 5)

Above response is not reproducible. Wondering if using random.randint() is reliable. Please let me know what caused this to occur or what other solution I can use for this problem.