def launchpadDistroPrefix(facet=None):
    if facet is None:
        prefix = ''
    else:
        prefix = '%s.' % facet
    distro = subprocess.Popen(['lsb_release', '--id', '--short'],
                              stdin=subprocess.PIPE,
                              stdout=subprocess.PIPE).communicate()[0].strip()
    distro = distro.replace(distro, 'Ubuntu')
    release = subprocess.Popen(['lsb_release', '--codename', '--short'],
                               stdin=subprocess.PIPE,
                               stdout=subprocess.PIPE).communicate()[0].strip()
    release = release.replace(release, 'gutsy')
    return 'https://%slaunchpad.net/%s/%s/' % (prefix, distro.lower(), release)