Question: when did the bhopal gas tragedy took place
[{'answer': '2 -- 3 December 1984'}, {'provenance': [{'wikipedia_id': '144638', 'title': 'Bhopal disaster', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 275, 'bleu_score': 0.773183843097056, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11181978343678103212}, 'section': 'Section::::Abstract.'}]}]