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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 push(self, instance, action, success, idxs=_marker):
 """Adds an instance into the pool, to be reindexed on resume """

        uid = api.get_uid(instance)
        info = self.objects.get(uid, {})
        idx = [] if idxs is _marker else idxs
        info[action] = {'success': success, 'idxs': idx}
        self.objects[uid] = info