Question: when was imperial bank was changed as sbi
[{'answer': '1955', 'provenance': [{'wikipedia_id': '2297597', 'title': 'Imperial Bank of India', 'start_paragraph_id': 1, 'start_character': 173, 'end_paragraph_id': 1, 'end_character': 177, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2297597', 'title': 'Imperial Bank of India', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 177, 'bleu_score': 0.878714225477435, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 1020995702574314804}, 'section': 'Section::::Abstract.'}]}]