Question: where is nuclear energy used most in the world
[{'answer': 'United States', 'provenance': [{'wikipedia_id': '5534701', 'title': 'Nuclear power by country', 'start_paragraph_id': 3, 'start_character': 4, 'end_paragraph_id': 3, 'end_character': 17, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'France', 'provenance': [{'wikipedia_id': '5534701', 'title': 'Nuclear power by country', 'start_paragraph_id': 3, 'start_character': 66, 'end_paragraph_id': 3, 'end_character': 72, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '5534701', 'title': 'Nuclear power by country', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 0, 'bleu_score': 1.0, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10484299131657777033}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '5534701', 'title': 'Nuclear power by country', 'section': 'Section::::Abstract.', 'start_paragraph_id': 3, 'end_paragraph_id': 3, 'meta': {'evidence_span': ['The United States is the largest producer of nuclear power, while France has the largest share of electricity generated by nuclear power.', 'The United States is the largest producer of nuclear power, while France has the largest share of electricity generated by nuclear power.', 'The United States is the largest producer of nuclear power, while France has the largest share of electricity generated by nuclear power.']}}]}]