 class="o">.</span><span class="n">Conv2d</span><span class="p">)</span> <span class="k">if</span> <span class="n">layer</span> <span class="ow">is</span> <span class="kc">None</span> <span class="k">else</span> <span class="n">layer</span>
        <span class="n">gradients_storage</span> <span class="o">=</span> <span class="n">BackwardModuleStorage</span><span class="p">([</span><span class="n">layer</span><span class="p">])</span>
        <span class="k">if</span> <span class="n">guide</span><span class=