...
RETRIEVE,
DATABASE = fdb5 prod,
NUMBER = 1/2/3/4/5/6/7/8/9/10/11/12/13/14/15/16/17/18/19/20/21/22/23/24/25/26/27/28/29/30/31/32/33/34/35/36/37/38/39/40/41/42/43/44/45/46/47/48/49/to/50,
AREA = 076/-015/050/045,
GRID = 0.18/0.18,
ACCURACY = 16,
TARGET = "mars_ens_[date]_[time]+[step].[number]",
CLASS = OD,
TYPE = PF,
DATE = -65,
TIME = 06,
STREAM = ENFO,
EXPVER = 1,
STEP = 6/to/5436/by/1,
LEVTYPE = ML,
LEVELIST = 1/to/91,
PARAM = Q/T/U/V/LNSP
...