s="p">(</span><span class="n">PDB_file</span><span class="p">,</span> <span class="n">flag_membrane</span> <span class="o">=</span> <span class="kc">False</span><span class="p">,</span> <span class="n">lam_bond</span> <span class="o">=</span> <span class="kc">None</span><span class="p">)</span>
</pre></div>
</div>
</div>
</div>
<div class="section" id="Add-the-force-field">
<h2>Add the force field<a class="headerlink" href="#Add-the-force-field" title="Permalink to this headline">¶</a></h2>
<p>In this exam