title: `final` keyword equivalent for variables in Python?
body: <p>I couldn't find documentation on an equivalent of Java's <code>final</code> in Python, is there such a thing?</p>
  
  <p>I'm creating a snapshot of an object (used for restoration if anything fails); once this backup variable is assigned, it should not be modified -- a final-like feature in Python would be nice for this.</p>