    <span class="c1"># Not NMEA</span>
            <span class="k">return</span> <span class="kc">None</span>

        <span class="c1"># Trim any leading characters before the NMEA sentence.</span>
        <span class="n">raw_data</span> <span class="o">=</span> <span class="n">raw_data</span><span class="p">[</span><span class="n">raw_data</span><span class="o">.</span><span class="n">index</span><span class="p">(</span><span class="s1">&#39;$&#39;</span><span class="p">):]</span>

        <span class="c1