Question: who sang the song let's get it on
[{'answer': 'Marvin Gaye', 'provenance': [{'wikipedia_id': '1680493', 'title': "Let's Get It On (song)", 'start_paragraph_id': 1, 'start_character': 60, 'end_paragraph_id': 1, 'end_character': 71, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1680493', 'title': "Let's Get It On (song)", 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 684, 'bleu_score': 0.9213140265485871, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 2785334728500721551}, 'section': 'Section::::Abstract.'}]}]