title: Type annotation for any collection of a particular type
body: <p>Is there a type annotation to specify &quot;any collection or generator whose items are of a given type&quot; using Python's type annotation system?</p>
  <p>I have a function that doesn't care if it gets a <code>list</code> or <code>tuple</code> <code>set</code> or <code>generator</code> or whatever, as long as it is a collection of instances of  a particular class.</p>