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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 _check_tcpdump():
 """ Return True if the tcpdump command can be started """

    with open(os.devnull, 'wb') as devnull:
        try:
            proc = subprocess.Popen([conf.prog.tcpdump, "--version"],
                                    stdout=devnull, stderr=subprocess.STDOUT)
        except OSError:
            return False

    if OPENBSD:
        # 'tcpdump --version' returns 1 on OpenBSD 6.4
        return proc.wait() == 1
    else:
        return proc.wait() == 0