Question: when did harley davidson buy back from amf
[{'answer': 'In 1981', 'provenance': [{'wikipedia_id': '14142', 'title': 'Harley-Davidson', 'start_paragraph_id': 49, 'start_character': 0, 'end_paragraph_id': 49, 'end_character': 7, 'bleu_score': 1.0, 'section': 'Section::::History.:Restructuring and revival.\n'}]}, {'provenance': [{'wikipedia_id': '14142', 'title': 'Harley-Davidson', 'start_paragraph_id': 49, 'start_character': 0, 'end_paragraph_id': 49, 'end_character': 180, 'bleu_score': 0.9402297675816911, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4401638605345367515}, 'section': 'Section::::History.:Restructuring and revival.\n'}]}]