                       step_size=2000., scale_fn=clr_fn,
                                scale_mode=&#39;cycle&#39;)
            model.fit(X_train, Y_train, callbacks=[clr])
        ```
    # Arguments
        base_lr: initial learning rate which is the
            lower boundary in the cycle.
        max_lr: upper boundary in the cycle. Functionally,
            it defines the cycle amplitude (max_lr - base_lr).
            The lr at any cycle is the sum of base_lr
            and some scaling of the ampli