title: What would a "frozen dict" be?
body: <ul>
  <li>A frozen set is a frozenset.  </li>
  <li>A frozen list could be a tuple.  </li>
  <li>What would a frozen dict be? An immutable, hashable dict.  </li>
  </ul>
  
  <p>I guess it could be something like <code>collections.namedtuple</code>, but that is more like a frozen-keys dict (a half-frozen dict). Isn't it?</p>
  
  <p>A "frozendict" should be a frozen dictionary, it should have <code>keys</code>, <code>values</code>, <code>get</code>, etc., and support <code>in</code>, <code>for</code>, etc.</p>
  
  <p>update :<br>
   * there it is : <a href="https://www.python.org/dev/peps/pep-0603" rel="noreferrer">https://www.python.org/dev/peps/pep-0603</a></p>