Question: what country is the largest producer of blueberries
[{'answer': 'United States', 'provenance': [{'wikipedia_id': '17598541', 'title': 'Blueberry', 'start_paragraph_id': 31, 'start_character': 238, 'end_paragraph_id': 31, 'end_character': 251, 'bleu_score': 1.0, 'section': 'Section::::Identification.\n'}]}]