Question: who did the navajo code talkers work for
[{'answer': 'the Marines', 'provenance': [{'wikipedia_id': '48877', 'title': 'Code talker', 'start_paragraph_id': 32, 'start_character': 415, 'end_paragraph_id': 32, 'end_character': 426, 'bleu_score': 1.0, 'section': 'Section::::Languages.:Navajo.\n'}]}, {'provenance': [{'wikipedia_id': '48877', 'title': 'Code talker', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 304, 'bleu_score': 0.7326063204266, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10248459570101501378}, 'section': 'Section::::Abstract.'}]}]