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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 updateLink(page, lnk):
 """ Update a link on the current page. """

    CheckParent(page)
    annot = getLinkText(page, lnk)
    if annot == "":
        raise ValueError("link kind not supported")

    page.parent._updateObject(lnk["xref"], annot, page = page) 
    return