Question: who is called as the policeman of europe
[{'answer': 'Nicholas I of Russia', 'provenance': [{'wikipedia_id': '9455794', 'title': 'List of nicknames of European royalty and nobility: N–O', 'start_paragraph_id': 26, 'start_character': 12, 'end_paragraph_id': 26, 'end_character': 32, 'bleu_score': 1.0, 'section': 'Section::::N.\n'}]}, {'provenance': [{'wikipedia_id': '9455794', 'title': 'List of nicknames of European royalty and nobility: N–O', 'start_paragraph_id': 26, 'start_character': 0, 'end_paragraph_id': 26, 'end_character': 153, 'bleu_score': 0.9146912192286941, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12585500848788434503}, 'section': 'Section::::N.\n'}]}]