Because len() is a global function. That&#x27;s perfectly fine in an OO system (everything does not have to be an object, attribute or method). Sure, it&#x27;s not as consistent as anything.len(), but it works just fine. That&#x27;s often the reason why Ruby claims to be a cleaner OO implementation than Python.<p>To me, Python really shows its warts when reversing a string. Something you never do out side of school (or on big ending to little endinan conversions).<p>In Python 2:<p><pre><code>    string[::-1]
</code></pre>
In Ruby:<p><pre><code>    string.reverse()
</code></pre>
Now that&#x27;s mind boggling and totally yucky.