Check if one of variables is set to None
<p>I recently had to implement a small check for any variables that might have not been initialized (and their default value is <code>None</code>). I came up with this:</p>

<pre><code>if None in (var1, var2, var3):
    error_out()
</code></pre>

<p>While, in my eyes, bordering on beautiful, I was wondering - is this a good way to do it? Is this <strong>the</strong> way to do it? Are there any cases in which this would produce some unexpected results?</p>
