lenskit.data.UserIDKey
======================

.. py:class:: lenskit.data.UserIDKey
   :canonical: lenskit.data._collection.UserIDKey

   Bases: :py:obj:`NamedTuple`


   Key type for user IDs.  This is used for :ref:`item list collections
   <item-list-collections>` that are keyed by user ID, a common setup for
   recommendation runs and test data.


   .. py:attribute:: user_id
      :type:  lenskit.data.types.ID