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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 CheckFont(page, fontname):
 """Return an entry in the page's font list if reference name matches. """

    for f in page.getFontList():
        if f[4] == fontname:
            return f
        if f[3].lower() == fontname.lower():
            return f
    return None