random stars in the console

stars.py

#!/usr/bin/python

import random

rows = 20
cols = 80
num_stars = 100
rand_stars = []

while (len(rand_stars) < num_stars):
    rand = random.randint(0, rows * cols)
    if rand not in rand_stars:
        rand_stars.append(rand)

count = 0
out = ''
for r in range(rows):
    for c in range(cols):
        if count in rand_stars:
            out += '*'
        else:
            out += ' '
        count = count + 1
    out += "\n"

print out