os.getenv("ZDTM_MNT_EXT_DEV") and \
( lambda dev, rdev:
{'flavor': 'ns', 'feature': 'mnt_id', "flags": "suid",
"dopts": "--external dev[%d/%d]:loop" % (os.major(rdev), os.minor(rdev)),
"ropts": "--external dev[loop]:%s" % dev,
} ) (os.getenv("ZDTM_MNT_EXT_DEV"), os.stat(os.getenv("ZDTM_MNT_EXT_DEV")).st_rdev) or {'flags': 'noauto'}
