train['Gender'].fillna(train['Gender'].mode()[0], inplace=True) : <pre><code>    train['Gender'].fillna(train['Gender'].mode()[0], inplace=True)
</code></pre>

<p>I got this code in one of my basic data science course. I wanted to understand, what is the significance of "[0]" after mode() in this. I would really appreciate the answer.
Thanks!</p>
