How many Call of Duty games have there been?
{'directed': True, 'multigraph': False, 'graph': {}, 'nodes': [{'type': 'INTERNAL', 'name_': 'Q652', 'id': 0, 'label': 'Italian'}, {'type': 'INTERNAL', 'name_': 'Q94', 'id': 1, 'label': 'Android'}, {'type': 'QUESTIONS_ENTITY', 'name_': 'Q192156', 'id': 2, 'label': 'Call of Duty'}, {'type': 'INTERNAL', 'name_': 'Q104419368', 'id': 3, 'label': 'Vita di Henri Brulard'}, {'type': 'ANSWER_CANDIDATE_ENTITY', 'name_': 'Q40292', 'id': 4, 'label': '20'}], 'links': [{'name_': 'P407', 'source': 1, 'target': 0, 'label': 'language of work or name'}, {'name_': 'P400', 'source': 2, 'target': 1, 'label': 'platform'}, {'name_': 'P407', 'source': 3, 'target': 0, 'label': 'language of work or name'}, {'name_': 'P747', 'source': 3, 'target': 4, 'label': 'has edition or translation'}]}