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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 enter(clsQname):
 """ Delegate a rule to another class which instantiates a Klein app This also memoizes the resource instance on the handler function itself """

    def wrapper(routeHandler):
        @functools.wraps(routeHandler)
        def inner(self, request, *a, **kw):
            if getattr(inner, '_subKlein', None) is None:
                cls = namedAny(clsQname)
                inner._subKlein = cls().app.resource()
            return routeHandler(self, request, inner._subKlein, *a, **kw)
        inner._subKleinQname = clsQname
        return inner
    return wrapper