k">except</span> <span class="ne">ImportError</span><span class="p">:</span>
    <span class="k">raise</span> <span class="ne">ImportError</span><span class="p">(</span><span class="s2">&quot;pymatgen.analysis.functional_groups requires the &quot;</span>
                      <span class="s2">&quot;NetworkX graph library to be installed.&quot;</span><span class="p">)</span>

<span class="n">__author__</span> <span class="o">=</span> <span class="s2">&quot;Evan Spotte-Smith&quot;</span>
<span class="n">__ver