Question: when did the first iditarod race take place
[{'answer': '1973', 'provenance': [{'wikipedia_id': '175114', 'title': 'Iditarod Trail Sled Dog Race', 'start_paragraph_id': 1, 'start_character': 314, 'end_paragraph_id': 1, 'end_character': 318, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '175114', 'title': 'Iditarod Trail Sled Dog Race', 'start_paragraph_id': 13, 'start_character': 0, 'end_paragraph_id': 13, 'end_character': 1102, 'bleu_score': 0.950241036940159, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4977141776043591786}, 'section': 'Section::::History.\n'}]}]