 mark it as &quot;set to null&quot; in the
$this-&gt;openAPINullablesSetToNull array</p>

    <code class="phpdocumentor-code phpdocumentor-signature ">
    <span class="phpdocumentor-signature__visibility">private</span>
                    <span class="phpdocumentor-signature__name">setIfExists</span><span>(</span><span class="phpdocumentor-signature__argument"><span class="phpdocumentor-signature__argument__return-type">string&nbsp;</span><span class="phpdocumentor-signature__argument__name">$variableNam