Question: when did the vikings first come to britain
[{'answer': '8 June 793', 'provenance': [{'wikipedia_id': '32538', 'title': 'Viking Age', 'start_paragraph_id': 5, 'start_character': 56, 'end_paragraph_id': 5, 'end_character': 66, 'bleu_score': 1.0, 'section': 'Section::::Historical considerations.\n'}]}, {'provenance': [{'wikipedia_id': '32538', 'title': 'Viking Age', 'start_paragraph_id': 5, 'start_character': 0, 'end_paragraph_id': 5, 'end_character': 468, 'bleu_score': 0.9321992460304711, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16535057356550289821}, 'section': 'Section::::Historical considerations.\n'}]}]