span class="nn">numpy</span> <span class="k">as</span> <span class="nn">np</span>
<span class="kn">import</span> <span class="nn">tensorflow</span> <span class="k">as</span> <span class="nn">tf</span>

<span class="kn">from</span> <span class="nn">cleverhans.attacks.attack</span> <span class="kn">import</span> <span class="n">Attack</span>
<span class="kn">from</span> <span class="nn">cleverhans.attacks.fast_gradient_method</span> <span class="kn">import</span> <span class="n">optimize_linear</span>
<span c