Question: who sings have you ever seen the rain
[{'answer': 'Creedence Clearwater Revival', 'provenance': [{'wikipedia_id': '12863717', 'title': 'Have You Ever Seen the Rain?', 'start_paragraph_id': 1, 'start_character': 150, 'end_paragraph_id': 1, 'end_character': 178, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '12863717', 'title': 'Have You Ever Seen the Rain?', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 613, 'bleu_score': 0.9825310706027971, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8476131692264651803}, 'section': 'Section::::Abstract.'}]}]