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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 hide_navbar_items(portal):
 """Hide root items in navigation """

    logger.info("*** Hide Navigation Items ***")

    # Get the list of object ids for portal
    object_ids = portal.objectIds()
    object_ids = filter(lambda id: id in object_ids, NAV_BAR_ITEMS_TO_HIDE)
    for object_id in object_ids:
        item = portal[object_id]
        item.setExcludeFromNav(True)
        item.reindexObject()