import tensorflow as tf

                    layers_ratio = (l + 1) / (L + 2)
                    drop_path_keep_prob = self._get_drop_path_keep_prob(layers_ratio, step, is_train, **knobs)

                    # Either add a reduction cell or normal cell
                    if l in reduction_layers:
                        block_ch *= 2
                        w >>= 1
                        h >>= 1

                        with tf.variable_scope('reduction_cell'):
                            if use_dynamic_arch:
                                self._add_dynamic_cell(reduction_arch, layers, w, h, block_ch, drop_path_keep_prob, is_train)
                            else:
                                self._add_static_cell(reduction_arch, layers, w, h, block_ch, drop_path_keep_prob, is_train,
                                                    is_reduction=True)
                    else:
                        with tf.variable_scope('normal_cell'):
                            if use_dynamic_arch:
