p">[</span><span class="n">i</span><span class="p">]:</span>
            <span class="n">atom_cluster</span> <span class="o">=</span> <span class="nb">set</span><span class="p">()</span>
            <span class="n">cluster</span> <span class="o">=</span> <span class="n">visit</span><span class="p">(</span><span class="n">i</span><span class="p">,</span> <span class="n">atom_cluster</span><span class="p">)</span>
            <span class="n">clusters</span><span class="o">.</span><span class="n">append</span>