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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 get_container_for(portal_type):
 """Returns the single holding container object of this content type :param portal_type: The portal type requested :type portal_type: string :returns: Folderish container where the portal type can be created :rtype: AT content object """

    container_paths = config.CONTAINER_PATHS_FOR_PORTAL_TYPES
    container_path = container_paths.get(portal_type)

    if container_path is None:
        return None

    portal_path = get_path(get_portal())
    return get_object_by_path("/".join([portal_path, container_path]))