Question: who won the battle of chancellorsville in the civil war
[{'answer': 'Confederate', 'provenance': [{'wikipedia_id': '48780', 'title': 'Battle of Chancellorsville', 'start_paragraph_id': 1, 'start_character': 493, 'end_paragraph_id': 1, 'end_character': 504, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]