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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 add(self, items):
 """Add entry to global presubs list"""

        with _presub_lock:
            self.load_from_cloud()
            for entry in utils.ensure_listable(items):
                # add new entries, but only if they're unique
                if entry not in self.current:
                    self.current.append(entry)
            self.save_to_cloud()