='hg19')
annotated = count(mapped, features=[{gene}])
</pre>
        <li>The user does not need to specify which annotation database to use
        in the second line, <em>as the reads had been mapped to hg19</em>.</li>
        <li>The language <em>knows which reference to map and to annotate with</em>.</li>
        <li>Some types of common mistakes (mismatched reference files, &amp;c) are <em>impossible or hard to express</em>.</li>
        <li>Tool can ship with or auto-download the necessary data depende