Question: what is the host nation of the 2004 summer olympic games
[{'answer': 'Athens , Greece', 'provenance': [{'wikipedia_id': '77741', 'title': '2004 Summer Olympics', 'start_paragraph_id': 1, 'start_character': 178, 'end_paragraph_id': 1, 'end_character': 193, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '77741', 'title': '2004 Summer Olympics', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 588, 'bleu_score': 0.535407213721883, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9057044075581585097}, 'section': 'Section::::Abstract.'}]}]