python - db.Time Property saving time as datetime instead of just time -

i using db.time property save time required conversion:

my_model.conversion_time = time_taken = datetime.datetime.strptime(str(conversion_end - conversion_start), "%h:%m:%s.%f").time() 

but when see data in datastore viewer , stored datetime object date of 1970-01-01. know how can save time in datastore

i'm not sure why have 2 inline assignments, time out of timedelta object:

>>> b datetime.datetime(2013, 7, 15, 10, 21, 31, 599402) >>> datetime.datetime(2013, 7, 15, 10, 18, 11, 251477) >>> str(b-a) '0:03:20.347925' >>> (datetime.datetime.min + (b-a)).time() datetime.time(0, 3, 20, 347925) 

in order store only time, need use timeproperty in datastore. represented internally datetime, store datetime.time() objects.