Question: what year was the mustang in the movie bullitt
[{'answer': '1968', 'provenance': [{'wikipedia_id': '433285', 'title': 'Bullitt', 'start_paragraph_id': 1, 'start_character': 13, 'end_paragraph_id': 1, 'end_character': 17, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '433285', 'title': 'Bullitt', 'start_paragraph_id': 51, 'start_character': 4, 'end_paragraph_id': 51, 'end_character': 736, 'bleu_score': 0.9112738398015471, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 1890056187336600401}, 'section': 'Section::::Production.:Car chase.:Filming.\n'}]}]