import tensorflow as tf

    decoder_depth: Integer, the filters used in the convolution.
    decoder_use_separable_conv: Boolean, use separable conv or not.
    weight_decay: Weight decay for the model variables.
    scope_suffix: String, used in the scope suffix.

  Returns:
    decoder features merged with concatenation.
  """
  if decoder_use_separable_conv:
    decoder_features = split_separable_conv2d(
        tf.concat(decoder_features_list, 3),
        filters=decoder_depth,
        rate=1,
        weight_decay=weight_decay,
        scope='decoder_conv0'+scope_suffix)
    decoder_features = split_separable_conv2d(
        decoder_features,
        filters=decoder_depth,
        rate=1,
        weight_decay=weight_decay,
