Question: where was the last 10 summer olympic games held
[{'answer': 'Rio de Janeiro', 'provenance': [{'wikipedia_id': '11015817', 'title': 'List of Olympic Games host cities', 'start_paragraph_id': 5, 'start_character': 300, 'end_paragraph_id': 5, 'end_character': 314, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'London', 'provenance': [{'wikipedia_id': '11015817', 'title': 'List of Olympic Games host cities', 'start_paragraph_id': 1, 'start_character': 558, 'end_paragraph_id': 1, 'end_character': 564, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Beijing', 'provenance': [{'wikipedia_id': '11015817', 'title': 'List of Olympic Games host cities', 'start_paragraph_id': 3, 'start_character': 108, 'end_paragraph_id': 3, 'end_character': 115, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Athens', 'provenance': [{'wikipedia_id': '11015817', 'title': 'List of Olympic Games host cities', 'start_paragraph_id': 1, 'start_character': 685, 'end_paragraph_id': 1, 'end_character': 691, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Sydney'}, {'answer': 'Atlanta'}, {'answer': 'Barcelona'}, {'answer': 'Seoul'}, {'answer': 'Los Angeles', 'provenance': [{'wikipedia_id': '11015817', 'title': 'List of Olympic Games host cities', 'start_paragraph_id': 3, 'start_character': 240, 'end_paragraph_id': 3, 'end_character': 251, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Moscow', 'provenance': [{'wikipedia_id': '11015817', 'title': 'List of Olympic Games host cities', 'start_paragraph_id': 19, 'start_character': 202, 'end_paragraph_id': 19, 'end_character': 208, 'bleu_score': 1.0, 'section': 'Section::::Notes.\n'}]}]