atomic systems that are used internally by the package.</span>
<span class="sd">    Inherits from the ase.Atoms class, but adds the possibility to cache</span>
<span class="sd">    various time-consuming quantities that can be shared when creating multiple</span>
<span class="sd">    descriptors.</span>
<span class="sd">    &quot;&quot;&quot;</span>
    <span class="k">def</span> <span class="fm">__init__</span><span class="p">(</span>
            <span class="bp">self</span><span class="p">,</span>
       