django models mongoengine not in filter

Django: NOT IN -> exclude(a__in=b_list)

NOT IN: nin

ne – not equal to
lt – less than
lte – less than or equal to
gt – greater than
gte – greater than or equal to
not – negate a standard check, may be used before other operators (e.g. Q(age__not__mod=5))
in – value is in list (a list of values should be provided)
nin – value is not in list (a list of values should be provided)
mod – value % x == y, where x and y are two provided values
all – every item in list of values provided is in array
size – the size of the array is
exists – value for field exists

Offical Docs: Querying the database