title: Equivalent to python's set.pop() for C++'s unordered sets
body: <p>Does C++ have an equivalent to python's <code>set.pop()</code>? I've been looking at the documentation for <code>unordered_set</code>s  <a href="http://www.cplusplus.com/reference/unordered_set/unordered_set/" rel="noreferrer">here</a>, but there doesn't seem to be a way to 1. Access an arbitrary element, and/or 2. Access + remove an arbitrary element (popping).</p>