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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 dispatch_hook(cls, _pkt=None, *args, **kargs):
 """ Returns the right parameter set class. """


        cls = conf.raw_layer
        if _pkt is not None:
            ptype = orb(_pkt[0])
            return globals().get(_param_set_cls.get(ptype), conf.raw_layer)

        return cls