Include required antl3 library and check if datastore is available
The datastore is checked for availability before requesting it to
be cleared. This is because gaeftest uses its own method for ensuring
no leakage of data by providing a temporary file as the backend.
Reviewed by: Sverre Rabbelier
"""
Field-like classes that aren't really fields. It's easier to use objects that
have the same attributes as fields sometimes (avoids a lot of special casing).
"""
from django.db.models import fields
class OrderWrt(fields.IntegerField):
"""
A proxy for the _order database field that is used when
Meta.order_with_respect_to is specified.
"""
name = '_order'
attname = '_order'
column = '_order'