Question: how many railway zones are there in india
[{'answer': '18', 'provenance': [{'wikipedia_id': '33238951', 'title': 'Zones and divisions of Indian Railways', 'start_paragraph_id': 1, 'start_character': 157, 'end_paragraph_id': 1, 'end_character': 159, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '33238951', 'title': 'Zones and divisions of Indian Railways', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 50, 'bleu_score': 0.8070557274927981, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14005328462121227469}, 'section': 'Section::::List of zones and its divisions.\n'}]}]