Question: who played the headless horseman in sleepy hollow movie
[{'answer': 'Christopher Walken', 'provenance': [{'wikipedia_id': '55601', 'title': 'Sleepy Hollow (film)', 'start_paragraph_id': 35, 'start_character': 1551, 'end_paragraph_id': 35, 'end_character': 1569, 'bleu_score': 1.0, 'section': 'Section::::Production.:Development.\n'}]}, {'answer': 'Ray Park', 'provenance': [{'wikipedia_id': '55601', 'title': 'Sleepy Hollow (film)', 'start_paragraph_id': 46, 'start_character': 408, 'end_paragraph_id': 46, 'end_character': 416, 'bleu_score': 1.0, 'section': 'Section::::Production.:Design.:Visual effects.\n'}]}, {'provenance': [{'wikipedia_id': '55601', 'title': 'Sleepy Hollow (film)', 'start_paragraph_id': 23, 'start_character': 12, 'end_paragraph_id': 23, 'end_character': 78, 'bleu_score': 0.534825931283887, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11179374676431346983}, 'section': 'Section::::Cast.\n'}]}]