bugfixes:
  - Set filters ``intersect``, ``difference``, ``symmetric_difference`` and ``union`` now use set operations when the given items are hashable.
    Previously, list operations were performed unless the inputs were a hashable type such as ``str``, instead of a collection, such as a ``list`` or ``tuple``.
  - Set filters ``intersect``, ``difference``, ``symmetric_difference`` and ``union`` now always return a ``list``, never a ``set``.
    Previously, a ``set`` would be returned if the inputs were a hashable type such as ``str``, instead of a collection, such as a ``list`` or ``tuple``.
minor_changes:
  - Documentation for set filters ``intersect``, ``difference``, ``symmetric_difference`` and ``union`` now states
    that the returned list items are in arbitrary order.
