span><span class="n">system</span><span class="p">,</span> <span class="n">Atoms</span><span class="p">):</span>
            <span class="n">n_atoms</span> <span class="o">=</span> <span class="nb">len</span><span class="p">(</span><span class="n">system</span><span class="p">)</span>
            <span class="n">indices</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_get_indices</span><span class="p">(</span><span class="n">n_atoms</span><span class="p">,