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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 expose(rule, **options):
 """Decorator to add an url rule to a function """

    def decorator(f):
        if not hasattr(f, "urls"):
            f.urls = []
        if isinstance(rule, (list, tuple)):
            f.urls.extend(rule)
        else:
            f.urls.append((rule, options))
        return f
    return decorator