def unscale_action(action_space, scaled_action):
    """
    Rescale the action from [-1, 1] to [low, high]
    (no need for symmetric action space)

    :param action_space: (gym.spaces.box.Box)
    :param action: (np.ndarray)
    :return: (np.ndarray)
    """
    low, high = action_space.low, action_space.high
    return low + 0.5 * (scaled_action + 1.0) * (high - low)
