Question: what were the names of the religious structures built by the sumerians
[{'answer': 'ziggurats', 'provenance': [{'wikipedia_id': '23410226', 'title': 'Sumerian religion', 'start_paragraph_id': 2, 'start_character': 416, 'end_paragraph_id': 2, 'end_character': 425, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '23410226', 'title': 'Sumerian religion', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 481, 'bleu_score': 0.9716239638199891, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8010529259530958959}, 'section': 'Section::::Abstract.'}]}]