Question: who played blanche dubois in streetcar named desire
[{'answer': 'Vivien Leigh', 'provenance': [{'wikipedia_id': '3367826', 'title': 'A Streetcar Named Desire (1951 film)', 'start_paragraph_id': 2, 'start_character': 338, 'end_paragraph_id': 2, 'end_character': 350, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '3367826', 'title': 'A Streetcar Named Desire (1951 film)', 'start_paragraph_id': 12, 'start_character': 0, 'end_paragraph_id': 12, 'end_character': 42, 'bleu_score': 0.6147881529512641, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14276116135467697387}, 'section': 'Section::::Cast.\n'}]}]