<code class="sourceCode R"><span><span class="co"># data.table</span></span>
<span><span class="va">flights</span><span class="op">[</span>, <span class="fu"><a href="https://rdrr.io/r/utils/head.html" class="external-link">head</a></span><span class="op">(</span><span class="va">.SD</span>, <span class="fl">2</span><span class="op">)</span>, by <span class="op">=</span> <span class="va">month</span><span class="op">]</span></span>
<span></span>
<span><span class="co"># tidyfst</span></span>
<span><span cla