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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 load(cls, data):
 """Create an object from JSON data. Parameters data : `dict` JSON data. Returns `object` Created object. Raises ------ KeyError If `data` does not have the '__class__' key or the necessary class is not in the class group. """

        ret = cls.classes[data['__class__']]
        data_cls = data['__class__']
        del data['__class__']
        try:
            ret = ret(**data)
        finally:
            data['__class__'] = data_cls
        return ret