    <span class="kn">import</span> <span class="nn">numpy</span> <span class="k">as</span> <span class="nn">np</span>
    <span class="kn">import</span> <span class="nn">matplotlib.pyplot</span> <span class="k">as</span> <span class="nn">plt</span>

    <span class="n">xf</span><span class="p">,</span> <span class="n">yf</span> <span class="o">=</span> <span class="n">AbsFFT</span><span class="p">(</span><span class="n">ts</span><span class="p">,</span> <span class="n">fs</span><span class="p">)</span>  <sp