What did Albert Einstein win in 1921?
{'directed': True, 'multigraph': False, 'graph': {}, 'nodes': [{'type': 'INTERNAL', 'name_': 'Q5', 'id': 0, 'label': 'human'}, {'type': 'QUESTIONS_ENTITY', 'name_': 'Q937', 'id': 1, 'label': 'Albert Einstein'}, {'type': 'ANSWER_CANDIDATE_ENTITY', 'name_': 'Q42299', 'id': 2, 'label': 'Bernhard Riemann'}], 'links': [{'name_': 'P1963', 'source': 0, 'target': 1, 'label': 'properties for this type'}, {'name_': 'P31', 'source': 2, 'target': 0, 'label': 'instance of'}]}