/rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="cn">TRUE</span><span class="op">)</span>,</span>
<span>                P<span class="op">=</span><span class="va">P_1PL</span> <span class="op">)</span></span>
<span><span class="co"># list of item classes in customItems</span></span>
<span><span class="va">customItems</span> <span class="op">&lt;-</span> <span class="fu"><a href="https://rdrr.io/r/base/list.html" class="external-link">list</a></span><span class=