What country has won the most Olympic medals?
{'directed': True, 'multigraph': False, 'graph': {}, 'nodes': [{'type': 'QUESTIONS_ENTITY', 'name_': 'Q636830', 'id': 0, 'label': 'Olympic medal'}, {'type': 'ANSWER_CANDIDATE_ENTITY', 'name_': 'Q7205677', 'id': 1, 'label': 'Category:Olympic medals'}], 'links': [{'name_': 'P910', 'source': 0, 'target': 1, 'label': "topic's main category"}, {'name_': 'P301', 'source': 1, 'target': 0, 'label': "category's main topic"}]}