title: How to set default value to all keys of a dict object in python?
body: <p>I know you can use setdefault(key, value) to set default value for a given key, but is there a way to set default values of all keys to some value after creating a dict ?</p>
  
  <p>Put it another way, I want the dict to return the specified default value for every key I didn't yet set.</p>