card simulation

from random import randint # randint(1, 13) returns a random integer between 1 and 13 inclusive.
from itertools import groupby # groups consecutive identical values of an iterable together

N = 5000 # number of simulations

def success(cards) :
    groups = list(list(g) for k,g in groupby(sorted(cards))) # ranks grouped...
    groups = list(reversed(sorted(groups, key=len))) # ... and sorted by decreasing length
    return len(groups[0]) == 3 and len(groups[1]) == 1 # implies len(groups[2]) == 1

def test_success() :
    assert success([5,5,5,7,6])
    assert success([4,3,4,1,4])
    assert not success([1,2,3,4,5])
    assert not success([3,3,3,4,4])

random_hand_ranks = lambda : [randint(1, 13) for _ in range(5)] # 5 random integers between 1 and 13 inclusive

def sim(store=True) :
    x_coords = []
    y_coords = []
    cnt = 0
    for x in range(N) :
        if success(random_hand_ranks()) :
            cnt += 1
        if store :
            x_coords.append(x)
            y_coords.append(cnt)
    return (x_coords, y_coords) if store else cnt

if input('Show graph? (Y)') == 'Y' :
    x,y = sim()
    import matplotlib.pyplot as plt
    plt.plot(x,y)
    plt.ylabel('Simulation succeses')
    plt.xlabel('Trials')
    plt.show()