'See :meth:`mopidy.core.LibraryController.get_images`.
*MAY be implemented by subclass.*
Default implementation will simply call lookup and try and use the
album art for any tracks returned. Most extensions should replace this
with something smarter or simply return an empty dictionary.'

def get_images(self, uris):

    result = {}
    for uri in uris:
        image_uris = set()
        for track in self.lookup(uri):
            if (track.album and track.album.images):
                image_uris.update(track.album.images)
        result[uri] = [models.Image(uri=u) for u in image_uris]
    return result
