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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 service_provider(*services):
 """ This is a class decorator that declares a class to provide a set of services. It is expected that the class has a no-arg constructor and will be instantiated as a singleton. """


    def real_decorator(clazz):
        instance = clazz()
        for service in services:
            global_lookup.add(service, instance)
        return clazz

    return real_decorator