 class="pre">&quot;ay&quot;,</span> <span class="pre">&quot;test_year&quot;,</span> <span class="pre">&quot;grade&quot;,</span> <span class="pre">&quot;category&quot;]</span></code> to join the two.</p>
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<div class="highlight-ipython3 notranslate"><div class="highlight"><pre><span></span><span class="n">ela2</span> <span class="o">=</span> <span class="n">ela</span><span class="o">.</span><span class="n">drop</span><span class=