zebra_puzzle.py

# Solving the interesting puzzle. You can check it out using
# https://en.wikipedia.org/wiki/Zebra_Puzzle Use this to 
# read about it

import itertools

def imright(h1, h2):
    "House h1 is immediately right of h2 if h1-h2 == 1."
    return h1-h2 == 1

def nextto(h1, h2):
    "Two houses are next to each other if they differ by 1."
    return abs(h1-h2) == 1

def zebra_puzzle():
    houses = first, _, middle, _, _ = [1, 2, 3, 4, 5]
    orderings = list(itertools.permutations(houses)) # 1
    return next((blue, oj)
                for (red, green, ivory, yellow, blue) in orderings
                if imright(green, ivory)
                for (Englishman, Spaniard, Ukranian, Japanese, Norwegian) in orderings
                if Englishman is red
                if Norwegian is first
                if nextto(Norwegian, blue)
                for (coffee, tea, milk, oj, water) in orderings
                if coffee is green
                if Ukranian is tea
                if milk is middle
                for (OldGold, Kools, Chesterfields, LuckyStrike, Parliaments) in orderings
                if Kools is yellow
                if LuckyStrike is oj
                if Japanese is Parliaments
                for (dog, snails, fox, horse, zebra) in orderings
                if Spaniard is dog
                if OldGold is snails
                if nextto(Chesterfields, fox)
                if nextto(Kools, horse)
                )

print(zebra_puzzle())