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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 tree(self, subject_ids=None, visit_ids=None, **kwargs):
 """ Return the tree of subject and sessions information within a project in the XNAT repository Parameters subject_ids : list(str) List of subject IDs with which to filter the tree with. If None all are returned visit_ids : list(str) List of visit IDs with which to filter the tree with. If None all are returned Returns ------- tree : arcana.repository.Tree A hierarchical tree of subject, session and fileset information for the repository """

        # Find all data present in the repository (filtered by the passed IDs)
        return Tree.construct(
            self, *self.find_data(subject_ids=subject_ids,
                                  visit_ids=visit_ids), **kwargs)