Question: who sings the opening to thursday night football
[{'answer': 'Pentatonix', 'provenance': [{'wikipedia_id': '7634921', 'title': 'Thursday Night Football', 'start_paragraph_id': 25, 'start_character': 188, 'end_paragraph_id': 25, 'end_character': 198, 'bleu_score': 1.0, 'section': 'Section::::Background.:2016–2017: CBS and NBC.\n'}]}, {'provenance': [{'wikipedia_id': '7634921', 'title': 'Thursday Night Football', 'start_paragraph_id': 25, 'start_character': 0, 'end_paragraph_id': 25, 'end_character': 517, 'bleu_score': 0.9766041382465441, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10942325896230232448}, 'section': 'Section::::Background.:2016–2017: CBS and NBC.\n'}]}]