from itertools import count
 
class CycleView:
    def __init__(self, seq):
        self.seq = seq
 
    def __getitem__(self, index):
        if isinstance(index, slice):
            return map(
                self.__getitem__,
                count(index.start) if index.stop is None
                else range(index.start or 0, index.stop)
            )
        return self.seq[index % len(self.seq)]
 
DEADVUL = 'x', 'y', 'z'
print(*CycleView(DEADVUL)[:10])
print(*CycleView(DEADVUL)[2000000000:2000000010])

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