Question: who was the prime minister of pakistan when martial law was imposed in 1958
[{'answer': 'General Ayub Khan', 'provenance': [{'wikipedia_id': '28865130', 'title': "1958 Pakistani coup d'état", 'start_paragraph_id': 5, 'start_character': 366, 'end_paragraph_id': 5, 'end_character': 383, 'bleu_score': 1.0, 'section': 'Section::::Martial law.\n'}]}, {'provenance': [{'wikipedia_id': '28865130', 'title': "1958 Pakistani coup d'état", 'start_paragraph_id': 5, 'start_character': 0, 'end_paragraph_id': 5, 'end_character': 571, 'bleu_score': 0.977139080690077, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4199183691447563934}, 'section': 'Section::::Martial law.\n'}]}]