def getManifestValueForKey(manifestpath, keyname):
    plist = getManifestData(manifestpath)
    try:
        return plist.get(keyname, None)
    except AttributeError, err:
        munkicommon.display_error(
            'Failed to get manifest value for key: %s (%s)',
            manifestpath, keyname)
        munkicommon.display_error(
            'Manifest is likely corrupt: %s', unicode(err))
        return None


# global to hold our catalog DBs
Returns a value for keyname in manifestpath
dataset/ETHPy150Open munki/munki/code/client/munkilib/updatecheck.py/getManifestValueForKey