Question: who directed the movie once upon a time in the west
[{'answer': 'Sergio Leone', 'provenance': [{'wikipedia_id': '284676', 'title': 'Once Upon a Time in the West', 'start_paragraph_id': 1, 'start_character': 143, 'end_paragraph_id': 1, 'end_character': 155, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '284676', 'title': 'Once Upon a Time in the West', 'start_paragraph_id': 1, 'start_character': 10, 'end_paragraph_id': 1, 'end_character': 552, 'bleu_score': 0.874796874891782, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10828400256310007725}, 'section': 'Section::::Abstract.'}]}]