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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def convert_json_file(obographfile, **args):
 """ Return a networkx MultiDiGraph of the ontologies serialized as a json string """

    f = open(obographfile, 'r')
    jsonstr = f.read()
    f.close()
    return convert_json_object(json.loads(jsonstr), **args)