How many spin-off games are in the Final Fantasy VII series?
{'directed': True, 'multigraph': False, 'graph': {}, 'nodes': [{'type': 'INTERNAL', 'name_': 'Q1860', 'id': 0, 'label': 'English'}, {'type': 'QUESTIONS_ENTITY', 'name_': 'Q214232', 'id': 1, 'label': 'Final Fantasy VII'}, {'type': 'INTERNAL', 'name_': 'Q112135185', 'id': 2, 'label': 'Exalted (1st ed.)'}, {'type': 'INTERNAL', 'name_': 'Q18613149', 'id': 3, 'label': 'Aeris Dies'}, {'type': 'ANSWER_CANDIDATE_ENTITY', 'name_': 'Q2294772', 'id': 4, 'label': 'Aerith Gainsborough'}], 'links': [{'name_': 'P407', 'source': 2, 'target': 0, 'label': 'language of work or name'}, {'name_': 'P2860', 'source': 2, 'target': 1, 'label': 'cites work'}, {'name_': 'P407', 'source': 3, 'target': 0, 'label': 'language of work or name'}, {'name_': 'P921', 'source': 3, 'target': 4, 'label': 'main subject'}]}