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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 clean(self):
 """Remove services without host object linked to Note that this should not happen! :return: None """

        to_del = []
        for serv in self:
            if not serv.host:
                to_del.append(serv.uuid)
        for service_uuid in to_del:
            del self.items[service_uuid]