import random

# flip a coin
random.choice([0, 1])

N = 100
flips = []
for i in range(N):
    flip = random.choice([0, 1])
    flips.append(flip)
    
print flips

print sum(flips) / float(len(flips))

hist(flips)

# write a function to perform many flips
def flip_N(N):
    flips = []
    for i in range(N):
        flip = random.choice([0, 1])
        flips.append(flip)
        
    return sum(flips) / float(N)

avg = flip_N(100)
print avg

# now perform many trials, and show the distribution
n_trials = 500
trials = []
N = 100

for i in range(n_trials):
    avg = flip_N(N)
    trials.append(avg)

hist(trials)

ls