Question: east african rift is what type of plate boundary
[{'answer': 'divergent tectonic plate boundary', 'provenance': [{'wikipedia_id': '2019833', 'title': 'East African Rift', 'start_paragraph_id': 2, 'start_character': 41, 'end_paragraph_id': 2, 'end_character': 74, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2019833', 'title': 'East African Rift', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 369, 'bleu_score': 0.798705568374347, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3540694052531063246}, 'section': 'Section::::Abstract.'}]}]