n><span class="n">dim</span><span class="o">=</span><span class="n">dims</span><span class="p">)</span> <span class="o">-</span> <span class="n">tensor</span><span class="o">.</span><span class="n">mean</span><span class="p">(</span><span class="n">dim</span><span class="o">=</span><span class="n">dims</span><span class="p">)</span> <span class="o">**</span> <span class="mi">2</span>
        <span class="n">tracker</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="