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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def initialize(album_cache, image_cache, albums, images):
 """Instantiate Album or Image instances not already in cache. :param dict album_cache: Cache of Imgur albums to update. Keys are Imgur IDs, values are Album instances. :param dict image_cache: Cache of Imgur images to update. Keys are Imgur IDs, values are Image instances. :param iter albums: List of album Imgur IDs. :param iter images: List of image Imgur IDs. :return: Same album and image cache dictionaries from parameters. :rtype: tuple """

    if not hasattr(album_cache, 'setdefault'):
        album_cache = dict()
    if not hasattr(image_cache, 'setdefault'):
        image_cache = dict()
    for imgur_id in albums:
        album_cache.setdefault(imgur_id, Album(imgur_id))
    for imgur_id in images:
        image_cache.setdefault(imgur_id, Image(imgur_id))
    return album_cache, image_cache