Advanced usage only: PHP code that returns the value to set. Should not include &lt;?php ?&gt; delimiters. If this field is filled out, the value returned by this code will override any value specified above. Expected format: <pre>!sample</pre>Using <a href="@link_devel">devel.module's</a> 'devel load' tab on a content page might help you figure out the expected format.