Question: who sings built this city on rock and roll
[{'answer': 'Mickey Thomas', 'provenance': [{'wikipedia_id': '1325588', 'title': 'We Built This City', 'start_paragraph_id': 4, 'start_character': 84, 'end_paragraph_id': 4, 'end_character': 97, 'bleu_score': 1.0, 'section': 'Section::::Content.\n'}]}, {'answer': 'Grace Slick', 'provenance': [{'wikipedia_id': '1325588', 'title': 'We Built This City', 'start_paragraph_id': 4, 'start_character': 102, 'end_paragraph_id': 4, 'end_character': 113, 'bleu_score': 1.0, 'section': 'Section::::Content.\n'}]}, {'provenance': [{'wikipedia_id': '1325588', 'title': 'We Built This City', 'start_paragraph_id': 4, 'start_character': 0, 'end_paragraph_id': 4, 'end_character': 1227, 'bleu_score': 0.9737023825578871, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11425389783874613501}, 'section': 'Section::::Content.\n'}]}]