Question: when did the us supreme court have 9 justices
[{'answer': '1869', 'provenance': [{'wikipedia_id': '31737', 'title': 'Supreme Court of the United States', 'start_paragraph_id': 2, 'start_character': 31, 'end_paragraph_id': 2, 'end_character': 35, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '31737', 'title': 'Supreme Court of the United States', 'start_paragraph_id': 28, 'start_character': 0, 'end_paragraph_id': 28, 'end_character': 375, 'bleu_score': 0.9699161750394991, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6177738561680416015}, 'section': 'Section::::Composition.:Size of the court.\n'}]}]