Question: when was oil discovered in the north sea
[{'answer': '1851', 'provenance': [{'wikipedia_id': '858340', 'title': 'North Sea oil', 'start_paragraph_id': 5, 'start_character': 11, 'end_paragraph_id': 5, 'end_character': 15, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '858340', 'title': 'North Sea oil', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 447, 'bleu_score': 0.941591348007749, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 2246757199898393343}, 'section': 'Section::::History.:1851–1963.\n'}]}]