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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 link_file(f, fldr):
 """ creates a html link for a file using folder fldr """

    fname = os.path.join(fldr,f)
    if os.path.isfile(fname):
        return '<a href="/aikif/data/core/' + f + '">' + f + '</a>'
    else:
        return f