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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(url_rule, endpoint=None, **kwargs):
 """Expose this function to the web layer."""


    def decorate(f):
        e = endpoint or f.__name__
        endpoints[e] = f
        url_map.add(Rule(url_rule, endpoint=e, **kwargs))
        return f

    return decorate