Question: what is the source if the nile river
[{'answer': 'Blue Nile', 'provenance': [{'wikipedia_id': '158338', 'title': 'Blue Nile', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 9, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'White Nile', 'provenance': [{'wikipedia_id': '158338', 'title': 'Blue Nile', 'start_paragraph_id': 1, 'start_character': 166, 'end_paragraph_id': 1, 'end_character': 176, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '158338', 'title': 'Blue Nile', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 311, 'bleu_score': 0.8882284427527001, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9519923390413996245}, 'section': 'Section::::Abstract.'}]}]