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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 _clean_check(cmd, target):
 """ Run the command to download target. If the command fails, clean up before re-raising the error. """

    try:
        subprocess.check_call(cmd)
    except subprocess.CalledProcessError:
        if os.access(target, os.F_OK):
            os.unlink(target)
        raise