2&#39;</span><span class="p">,</span><span class="s1">&#39;col3&#39;</span><span class="p">])</span>

<span class="c1"># check that col0 is removed as it only has 2 unique values and a low std value (0.040825)</span>
<span class="k">assert</span> <span class="s1">&#39;col0&#39;</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">drop_low_std_cols</span><span class="p">(</span><span class="n">df</span><span class="p">,</span> <span class="n">std_thold</span><span class="o">=</span><