Question: who was involved in the battle of barnet
[{'answer': 'Edward IV', 'provenance': [{'wikipedia_id': '50072', 'title': 'Battle of Barnet', 'start_paragraph_id': 1, 'start_character': 210, 'end_paragraph_id': 1, 'end_character': 219, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Hertfordshire', 'provenance': [{'wikipedia_id': '50072', 'title': 'Battle of Barnet', 'start_paragraph_id': 1, 'start_character': 264, 'end_paragraph_id': 1, 'end_character': 277, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'House of Lancaster', 'provenance': [{'wikipedia_id': '50072', 'title': 'Battle of Barnet', 'start_paragraph_id': 1, 'start_character': 352, 'end_paragraph_id': 1, 'end_character': 370, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Richard Neville , 16th Earl of Warwick'}, {'provenance': [{'wikipedia_id': '50072', 'title': 'Battle of Barnet', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 765, 'bleu_score': 0.967405819735595, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 13150156067937351812}, 'section': 'Section::::Abstract.'}]}]