How many leaders has South Korea had since 1945 that aligned with the "Independent" political party?
{'directed': True, 'multigraph': False, 'graph': {}, 'nodes': [{'type': 'QUESTIONS_ENTITY', 'name_': 'Q327591', 'id': 0, 'label': 'independent politician'}, {'type': 'INTERNAL', 'name_': 'Q458', 'id': 1, 'label': 'European Union'}, {'type': 'QUESTIONS_ENTITY', 'name_': 'Q884', 'id': 2, 'label': 'South Korea'}, {'type': 'INTERNAL', 'name_': 'Q1253', 'id': 3, 'label': 'Ban Ki-moon'}, {'type': 'INTERNAL', 'name_': 'Q7210356', 'id': 4, 'label': 'political organization'}, {'type': 'ANSWER_CANDIDATE_ENTITY', 'name_': 'Q11744698', 'id': 5, 'label': 'parliamentary grouping'}], 'links': [{'name_': 'P31', 'source': 0, 'target': 4, 'label': 'instance of'}, {'name_': 'P279', 'source': 0, 'target': 5, 'label': 'subclass of'}, {'name_': 'P530', 'source': 1, 'target': 2, 'label': 'diplomatic relation'}, {'name_': 'P31', 'source': 1, 'target': 4, 'label': 'instance of'}, {'name_': 'P102', 'source': 3, 'target': 0, 'label': 'member of political party'}, {'name_': 'P27', 'source': 3, 'target': 2, 'label': 'country of citizenship'}, {'name_': 'P279', 'source': 5, 'target': 4, 'label': 'subclass of'}]}