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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 epubcheck_help():
 """Return epubcheck.jar commandline help text. :return unicode: helptext from epubcheck.jar """


    # tc = locale.getdefaultlocale()[1]

    with open(os.devnull, "w") as devnull:
        p = subprocess.Popen(
            [c.JAVA, '-Duser.language=en', '-jar', c.EPUBCHECK, '-h'],
            stdout=subprocess.PIPE,
            stderr=devnull,
        )
        result = p.communicate()[0]

    return result.decode()