span> <span class="nf">exchange_correlation_potential</span><span class="p">(</span>
    <span class="n">s</span><span class="p">:</span> <span class="n">iDEA</span><span class="o">.</span><span class="n">system</span><span class="o">.</span><span class="n">System</span><span class="p">,</span> <span class="n">n</span><span class="p">:</span> <span class="n">np</span><span class="o">.</span><span class="n">ndarray</span><span class="p">,</span> <span class="n">separate</span><span class="p">:</span> <span c