'B': "{:0<4.0f}" | How should I read this?
<p>While studying <a href="http://pandas.pydata.org/pandas-docs/stable/style.html" rel="nofollow">Pandas Style</a>, I got to the following:</p>

<pre><code>df.style.format("{:.2%}")
</code></pre>

<p>Which I understand means, turn every value to 2 decimal places and add a <code>%</code> in the end.</p>

<p>Just after that, there is:</p>

<pre><code>df.style.format({'B': "{:0&lt;4.0f}", 'D': '{:+.2f}'})
</code></pre>

<p>How should I read <code>'B': "{:0&lt;4.0f}"</code>?</p>