import tensorflow as tf

                    target_params = tf_util.get_trainable_vars("target/values_fn/vf")

                    # Polyak averaging for target variables
                    self.target_update_op = [
                        tf.assign(target, (1 - self.tau) * target + self.tau * source)
                        for target, source in zip(target_params, source_params)
                    ]
                    # Initializing target to match source variables
