from __future__ import division, print_function
 
import random
 
balls = ['R', 'R', 'R', 'B']
 
two_red = 0
one_red = 0
 
for i in xrange(10000):
    balls_taken = random.sample(balls, 2)
    looked_at = random.choice(balls_taken)
    if looked_at == 'B':
        continue
    elif balls_taken.count('R') == 2:
        two_red += 1
    else:
        one_red += 1
 
print('Times we took two red and looked at a red ball:', two_red)
print('Times we took one red and looked at a red ball:', one_red)
print('Probability the other ball is red:', two_red / (one_red + two_red))

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