Question: when did the baiji river dolphin become extinct
[{'answer': 'late 2006', 'provenance': [{'wikipedia_id': '19109106', 'title': 'Baiji', 'start_paragraph_id': 2, 'start_character': 498, 'end_paragraph_id': 2, 'end_character': 507, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '19109106', 'title': 'Baiji', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 1118, 'bleu_score': 0.988731944750971, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 18375720925625901731}, 'section': 'Section::::Abstract.'}]}]