def test_update():
parent = Parent()
parent.save()
assert parent.id != None
assert Parent.objects.count() == 4
# Update
child = Child()
child.save()
assert child.parent_id is None
child.parent_id = parent.id
child.save()
assert Child.objects.count() == 22
assert child.parent_id == parent.id
def test_save():
parent = Parent()
parent.save()
assert parent.id is not None
assert Parent.objects.count() == 3
