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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 defaultMachine(use_rpm_default=True):
 """ Return the canonicalized machine name. """


    if use_rpm_default:
        try:
            # This should be the most reliable way to get the default arch
            rmachine = subprocess.check_output(['rpm', '--eval=%_target_cpu'], shell=False).rstrip()
            rmachine = SCons.Util.to_str(rmachine)
        except Exception as e:
            # Something went wrong, try again by looking up platform.machine()
            return defaultMachine(False)
    else:
        rmachine = platform.machine()

        # Try to lookup the string in the canon table
        if rmachine in arch_canon:
            rmachine = arch_canon[rmachine][0]

    return rmachine