n> <span class="n">body</span><span class="p">,</span> <span class="p">(</span><span class="n">tf</span><span class="o">.</span><span class="n">zeros</span><span class="p">([]),</span> <span class="n">adv_x</span><span class="p">,</span> <span class="n">momentum</span><span class="p">),</span> <span class="n">back_prop</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span>
        <span class="n">maximum_iterations</span><span class="o">=</span><span class="bp">self</span><span c