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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 get_object_closure(subject, object_category=None, **kwargs):
 """ Find all terms used to annotate subject plus ancestors """

    results = search_associations(subject=subject,
                                  object_category=object_category,
                                  select_fields=[],
                                  facet_fields=[M.OBJECT_CLOSURE],
                                  facet_limit=-1,
                                  rows=0,
                                  **kwargs)
    return set(results['facet_counts'][M.OBJECT_CLOSURE].keys())