<span class="nb">type</span><span class="p">(</span><span class="n">cols_to_drop</span><span class="p">)</span> <span class="o">==</span> <span class="nb">list</span>
    <span class="n">actual_cols_to_drop</span> <span class="o">=</span> <span class="p">[]</span>
    <span class="k">for</span> <span class="n">col</span> <span class="ow">in</span> <span class="n">cols_to_drop</span><span class="p">:</span>
        <span class="k">if</span> <span class="n">col</span> <span class="ow">in</span> <span class="b