import tensorflow as tf

    :return: ([TensorFlow Tensor]) the target Q-retrace
    """
    rho_bar = batch_to_seq(tf.minimum(1.0, rho_i), n_envs, n_steps, True)  # list of len steps, shape [n_envs]
    reward_seq = batch_to_seq(rewards, n_envs, n_steps, True)  # list of len steps, shape [n_envs]
