'create a new neural net object from the architecture specified in json_file'

@staticmethod
def load_model(json_file):

    with open(json_file, 'r') as f:
        object_specs = json.load(f)
    class_name = object_specs.get('class', 'CNNPolicy')
    try:
        network_class = NeuralNetBase.subclasses[class_name]
    except KeyError:
        raise ValueError('Unknown    neural    network    type    in    json    file:    {}\n(was    it    registered    with    the    @neuralnet    decorator?)'.format(class_name))
    new_net = network_class(object_specs['feature_list'], init_network=False)
    new_net.model = model_from_json(object_specs['keras_model'], custom_objects={'Bias': Bias})
    if ('weights_file' in object_specs):
        new_net.model.load_weights(object_specs['weights_file'])
    new_net.forward = new_net._model_forward()
    return new_net
