Question: who sings the theme song on that 70's show
[{'answer': 'Todd Griffin', 'provenance': [{'wikipedia_id': '274551', 'title': "That '70s Show", 'start_paragraph_id': 40, 'start_character': 99, 'end_paragraph_id': 40, 'end_character': 111, 'bleu_score': 1.0, 'section': 'Section::::Production.:Opening.:Theme song.\n'}]}, {'answer': 'Cheap Trick', 'provenance': [{'wikipedia_id': '274551', 'title': "That '70s Show", 'start_paragraph_id': 40, 'start_character': 241, 'end_paragraph_id': 40, 'end_character': 252, 'bleu_score': 1.0, 'section': 'Section::::Production.:Opening.:Theme song.\n'}]}, {'provenance': [{'wikipedia_id': '274551', 'title': "That '70s Show", 'start_paragraph_id': 40, 'start_character': 0, 'end_paragraph_id': 40, 'end_character': 417, 'bleu_score': 0.974188104609039, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12708324753475362184}, 'section': 'Section::::Production.:Opening.:Theme song.\n'}]}]