lass="nb">len</span><span class="p">(</span><span class="n">sys</span><span class="p">)</span>
            <span class="n">indices</span><span class="o">.</span><span class="n">append</span><span class="p">(</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">,</span> <span class="n">inc</span><span class="p">,</span> <span class="n">exc</span><span class="p">))</span>

        <span class="c1"># C