Question: who was the first elected president of nigeria
[{'answer': 'Nnamdi Azikiwe', 'provenance': [{'wikipedia_id': '516088', 'title': 'President of Nigeria', 'start_paragraph_id': 1, 'start_character': 332, 'end_paragraph_id': 1, 'end_character': 346, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '516088', 'title': 'President of Nigeria', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 537, 'bleu_score': 0.7796467268290991, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16948863799018046973}, 'section': 'Section::::Abstract.'}]}]