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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 static_data(fn):
 """ Static file handler. This functions accesses all static files in ``static`` directory. """

    file_path = os.path.normpath(fn)
    full_path = os.path.join(STATIC_PATH, file_path)

    if not os.path.exists(full_path):
        abort(404, "Soubor '%s' neexistuje!" % fn)

    return static_file(
        file_path,
        STATIC_PATH
    )