Question: how many times has the us formally declared war
[{'answer': 'five', 'provenance': [{'wikipedia_id': '455614', 'title': 'Declaration of war by the United States', 'start_paragraph_id': 7, 'start_character': 68, 'end_paragraph_id': 7, 'end_character': 72, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '455614', 'title': 'Declaration of war by the United States', 'start_paragraph_id': 11, 'start_character': 0, 'end_paragraph_id': 11, 'end_character': 349, 'bleu_score': 0.9669306597086381, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 7565772684842303454}, 'section': 'Section::::Declarations of war.:Formal.\n'}]}]