## tensorflow 2.8 code


import os
from tensorflow import keras


class CircleLayer(keras.layers.Layer):
    def __init__(self, **kwargs):
        super().__init__(**kwargs)

    def call(self, inputs):
        return inputs * 3.1415

    def get_config(self):
        return super().get_config()


def get_model():
    inputs = keras.layers.Input((6,))
    circle = CircleLayer(name="circle")
    outputs = circle(inputs)
    return keras.models.Model(inputs, outputs)


def save_model(model, path):
    cfg_file = os.path.join(path, f"{model.name}.json")
    with open(cfg_file, "w") as fp:
        fp.write(model.to_json(indent=2, sort_keys=True))
    weights_file = os.path.join(path, f"{model.name}.h5")
    model.save_weights(weights_file, overwrite=True)


if __name__ == "__main__":
    model_dir = "/tmp/tmp"
    os.makedirs(model_dir, exist_ok=True)
    model = get_model()
    save_model(model, model_dir)