Question: who played shaggy in the original scooby doo
[{'answer': 'Casey Kasem', 'provenance': [{'wikipedia_id': '920030', 'title': 'Shaggy Rogers', 'start_paragraph_id': 4, 'start_character': 1410, 'end_paragraph_id': 4, 'end_character': 1421, 'bleu_score': 1.0, 'section': 'Section::::Character description.\n'}]}]