import tensorflow as tf

        Based on: https://github.com/gitlimlab/CycleGAN-Tensorflow/blob/master/ops.py
        For tf padding, refer to: https://www.tensorflow.org/api_docs/python/tf/pad

    """
    reg_l2 = tf.keras.regularizers.l2(5e-7)

    if padding == 'SYMMETRIC' or padding == 'REFLECT':
        p = (kernel_size - 1) // 2
