Question: when did the snakehead fish arrive in the us
[{'answer': '2002', 'provenance': [{'wikipedia_id': '2495632', 'title': 'Snakehead (fish)', 'start_paragraph_id': 11, 'start_character': 7, 'end_paragraph_id': 11, 'end_character': 11, 'bleu_score': 1.0, 'section': 'Section::::Ecological concerns.\n'}]}, {'provenance': [{'wikipedia_id': '2495632', 'title': 'Snakehead (fish)', 'start_paragraph_id': 20, 'start_character': 0, 'end_paragraph_id': 20, 'end_character': 376, 'bleu_score': 0.8164380281458351, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 5508159868939932254}, 'section': 'Section::::Ecological concerns.:Reported sightings.:In the United States.\n'}]}]