Question: how many seasons was walker texas ranger on tv
[{'answer': '8', 'provenance': [{'wikipedia_id': '391455', 'title': 'Walker, Texas Ranger', 'start_paragraph_id': 1, 'start_character': 496, 'end_paragraph_id': 1, 'end_character': 497, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]