Generate symbolic graph for adversarial examples and return.

    :param x: The model's symbolic inputs.
    :param kwargs: See `parse_params`

def generate(self, x, **kwargs):
    """
    Generate symbolic graph for adversarial examples and return.

    :param x: The model's symbolic inputs.
    :param kwargs: See `parse_params`
    """
    assert self.sess is not None, \
        'Cannot use `generate` when no `sess` was provided'
    from cleverhans.utils_tf import jacobian_graph

    # Parse and save attack-specific parameters
    assert self.parse_params(**kwargs)

    # Define graph wrt to this input placeholder
    logits = self.model.get_logits(x)
    self.nb_classes = logits.get_shape().as_list()[-1]
    assert self.nb_candidate <= self.nb_classes, \
        'nb_candidate should not be greater than nb_classes'
    preds = tf.reshape(
        tf.nn.top_k(logits, k=self.nb_candidate)[0],
        [-1, self.nb_candidate])
    # grads will be the shape [batch_size, nb_candidate, image_size]
    grads = tf.stack(jacobian_graph(preds, x, self.nb_candidate), axis=1)

    # Define graph
    def deepfool_wrap(x_val):
      """deepfool function for py_func"""
      return deepfool_batch(self.sess, x, preds, logits, grads, x_val,
                            self.nb_candidate, self.overshoot,
                            self.max_iter, self.clip_min, self.clip_max,
                            self.nb_classes)

    wrap = tf.py_func(deepfool_wrap, [x], self.tf_dtype)
    wrap.set_shape(x.get_shape())
    return wrap