Trying to make a simple random number generator [closed]

I'm super new to python and I'm just trying to make a very simple random number generator function, but nothing seems to be working, and python just gives me an error every time. Could anyone help with this?

def roll_dice(num):
    return random.randint(1, num)

roll_dice(6)

Error Message:

NameError: name 'random' is not defined