oncatenate</span><span class="p">((</span><span class="n">idx1</span><span class="p">,</span> <span class="n">idx1_</span><span class="p">))</span>
        <span class="n">idx2</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">concatenate</span><span class="p">((</span><span class="n">idx2</span><span class="p">,</span> <span class="n">idx2_</span><span class="p">))</span>
        <span class="n">idx</span> <span class="o">=</span> <span class="n">np</span><spa