Question: what was the first atomic bomb made out of
[{'answer': 'uranium', 'provenance': [{'wikipedia_id': '18597', 'title': 'Little Boy', 'start_paragraph_id': 1, 'start_character': 594, 'end_paragraph_id': 1, 'end_character': 601, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '18597', 'title': 'Little Boy', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 618, 'bleu_score': 0.6650494132100551, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15879980041924269542}, 'section': 'Section::::Abstract.'}]}]