for-loop-anatomy-11.py

import random

class RandomWalk:
    def __init__(self, iterable):
        self.values = list(iterable)

    def __iter__(self):
        return RandomWalkIterator(self)

class RandomWalkIterator:
    def __init__(self, random_walk):
        self.random_walk = random_walk
        self.random_indices = list(
            range(len(random_walk.values))
        )
        random.shuffle(self.random_indices)
        self.idx = 0

    def __iter__(self):
        return self

    def __next__(self):
        if self.idx >= len(self.random_indices):
            raise StopIteration
        output = self.random_walk.values[
            self.random_indices[self.idx]
        ]
        self.idx += 1
        return output


captains = RandomWalk(
    [
        "Pike",
        "Kirk",
        "Picard",
        "Sisko",
        "Janeway",
        "Riker",
    ]
)

for captain in captains:
    print(captain)