>+</span> <span class="n">old_BILL_AMT</span> <span class="o">+</span> <span class="n">old_PAY</span><span class="p">,</span> <span class="n">axis</span><span class="o">=</span><span class="mi">1</span><span class="p">,</span> <span class="n">inplace</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span>

<span class="c1"># Creating the train/test split</span>
<span class="n">feature_names</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span c