Question: how many planet of the apes films has there been
[{'answer': '9', 'provenance': [{'wikipedia_id': '24404702', 'title': 'Planet of the Apes', 'start_paragraph_id': 1, 'start_character': 264, 'end_paragraph_id': 1, 'end_character': 265, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]