Question: when did the new £1 coins come into circulation
[{'answer': '28 March 2017', 'provenance': [{'wikipedia_id': '200442', 'title': 'One pound (British coin)', 'start_paragraph_id': 2, 'start_character': 459, 'end_paragraph_id': 2, 'end_character': 472, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]