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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 output(self):
 """ Returns the default workflow outputs in an ordered dictionary. At the moment this is just the collection of outputs of the branch tasks, stored with the key ``"collection"``. """

        if self.task.target_collection_cls is not None:
            cls = self.task.target_collection_cls
        elif self.task.outputs_siblings:
            cls = SiblingFileCollection
        else:
            cls = TargetCollection

        targets = luigi.task.getpaths(self.task.get_branch_tasks())
        collection = cls(targets, threshold=self.threshold(len(targets)))

        return OrderedDict([("collection", collection)])