Question: when did the supreme court ruled that bus segregation was unconstitutional
[{'answer': 'November 13 , 1956', 'provenance': [{'wikipedia_id': '151226', 'title': 'Montgomery bus boycott', 'start_paragraph_id': 39, 'start_character': 353, 'end_paragraph_id': 39, 'end_character': 371, 'bleu_score': 1.0, 'section': 'Section::::History.:Victory.\n'}]}, {'provenance': [{'wikipedia_id': '151226', 'title': 'Montgomery bus boycott', 'start_paragraph_id': 39, 'start_character': 0, 'end_paragraph_id': 39, 'end_character': 504, 'bleu_score': 0.9757530668325981, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 2103303753017919529}, 'section': 'Section::::History.:Victory.\n'}]}]