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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def iso_register(iso_code):
 """ Registers Calendar class as country or region in IsoRegistry. Registered country must set class variables ``iso`` using this decorator. Region calendar is then retrievable from registry: """

    def wrapper(cls):
        registry.register(iso_code, cls)
        return cls
    return wrapper