import tensorflow as tf

                else:
                    # Do not perturb, just assign.
                    op = tf.assign(perturbed_var, var)
                perturb_ops.append(op)
            assert len(perturb_ops) == len(all_vars)
            return tf.group(*perturb_ops)

        # Set up functionality to re-compute `param_noise_scale`. This perturbs yet another copy
        # of the network and measures the effect of that perturbation in action space. If the perturbation
        # is too big, reduce scale of perturbation, otherwise increase.
