Question: who played buck barrow in bonnie and clyde
[{'answer': 'Gene Hackman', 'provenance': [{'wikipedia_id': '68245', 'title': 'Bonnie and Clyde (film)', 'start_paragraph_id': 1, 'start_character': 223, 'end_paragraph_id': 1, 'end_character': 235, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '68245', 'title': 'Bonnie and Clyde (film)', 'start_paragraph_id': 13, 'start_character': 0, 'end_paragraph_id': 13, 'end_character': 39, 'bleu_score': 0.6147881529512641, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3014653139997595116}, 'section': 'Section::::Cast.\n'}]}]