an class="n">MoleculeGraph</span>
<span class="kn">from</span> <span class="nn">pymatgen.analysis.local_env</span> <span class="kn">import</span> <span class="n">OpenBabelNN</span>

<span class="k">try</span><span class="p">:</span>
    <span class="kn">import</span> <span class="nn">networkx</span> <span class="k">as</span> <span class="nn">nx</span>
    <span class="kn">import</span> <span class="nn">networkx.algorithms.isomorphism</span> <span class="k">as</span> <span class="nn">iso</span>
<span class="