>df</span><span class="o">.</span><span class="n">columns</span> <span class="k">if</span> <span class="s1">&#39;10&#39;</span> <span class="ow">in</span> <span class="n">c</span> <span class="ow">and</span> <span class="s1">&#39;brain&#39;</span> <span class="ow">in</span> <span class="n">c</span> <span class="ow">and</span> <span class="s1">&#39;signal&#39;</span> <span class="ow">in</span> <span class="n">c</span><span class="p">]</span>  <span class="c1"># i.e. only do brain at E10 samples</span>
<span 