monty_hall.py

#!/bin/env python3
import random

def get_random_exclude(*n):
    while True:
        ran = random.randint(0,2)
        if ran not in n:
            return ran

def montyhall(first_behaviour, second_behaviour):
    doors = [False, False, False]
    doors[random.randint(0,2)] = True
    car = doors.index(True)

    # First user decission
    user1 = first_behaviour()
    
    # Host shows a goat
    host1 = get_random_exclude(user1, car)
    
    # User decides again (he must know his first decission and the door where the goat is)
    user2 = second_behaviour(user1, host1)
    
    return doors[user2]
    
def test(n, behaviour):
    results = {True: 0, False: 0}
    if behaviour is "change":
        behaviour = lambda x,y: ({x, y} ^ {0,1,2}).pop()
    elif behaviour is "keep":
        behaviour = lambda x, y: x    

    for i in range(0, n):
        result = montyhall(lambda: random.randint(0,2), behaviour)
        results[result] += 1
        
    print(results)

Run with:

import monty_hall
monty_hall.test(1000000, "change")

or

import monty_hall
monty_hall.test(1000000, "keep")