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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_storage(clear=False):
 """helper function to get annotation storage on the portal :param clear: If true is passed in, annotations will be cleared :returns: portal annotations :rtype: IAnnotations """

    portal = getUtility(ISiteRoot)
    annotations = IAnnotations(portal)
    if ANNOTATION_KEY not in annotations or clear:
        annotations[ANNOTATION_KEY] = OOBTree()
    return annotations[ANNOTATION_KEY]