Question: who played in last year's fa cup final
[{'answer': 'Arsenal', 'provenance': [{'wikipedia_id': '53844268', 'title': '2017 FA Cup Final', 'start_paragraph_id': 1, 'start_character': 209, 'end_paragraph_id': 1, 'end_character': 216, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Chelsea', 'provenance': [{'wikipedia_id': '53844268', 'title': '2017 FA Cup Final', 'start_paragraph_id': 1, 'start_character': 221, 'end_paragraph_id': 1, 'end_character': 228, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '53844268', 'title': '2017 FA Cup Final', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 392, 'bleu_score': 0.9226596185977011, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17074098832812719979}, 'section': 'Section::::Abstract.'}]}]