Question: how many seasons of las vegas tv series
[{'answer': '5', 'provenance': [{'wikipedia_id': '322146', 'title': 'Las Vegas (TV series)', 'start_paragraph_id': 1, 'start_character': 98, 'end_paragraph_id': 1, 'end_character': 99, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]