Question: who sings the theme song of the wonder years
[{'answer': 'Joe Cocker', 'provenance': [{'wikipedia_id': '142892', 'title': 'The Wonder Years', 'start_paragraph_id': 50, 'start_character': 70, 'end_paragraph_id': 50, 'end_character': 80, 'bleu_score': 1.0, 'section': 'Section::::Title sequence.\n'}]}, {'provenance': [{'wikipedia_id': '142892', 'title': 'The Wonder Years', 'start_paragraph_id': 68, 'start_character': 0, 'end_paragraph_id': 68, 'end_character': 504, 'bleu_score': 0.767169631495183, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15541121576918273731}, 'section': 'Section::::Home media.:DVD music replacements.\n'}]}]