Exception: 'Node' object is not iterable

[Andres Rodriguez]

i upgraded MAAS to the latest trunk rev of 1.10 and started seeing the following enlistment issues:

2016-02-08 20:55:53 [-] 127.0.0.1 - - [08/Feb/2016:20:55:53 +0000] "POST /MAAS/api/1.0/nodes/ HTTP/1.1" 500 29 "-" "curl/7.35.0"
2016-02-08 20:55:54 [maasserver] ERROR: ################################ Exception: 'Node' object is not iterable ################################
2016-02-08 20:55:54 [maasserver] ERROR: Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/django/core/handlers/base.py", line 132, in get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "/usr/lib/python3/dist-packages/maasserver/utils/views.py", line 180, in view_atomic_with_post_commit_savepoint
    return view_atomic(*args, **kwargs)
  File "/usr/lib/python3.5/contextlib.py", line 30, in inner
    return func(*args, **kwds)
  File "/usr/lib/python3/dist-packages/maasserver/api/support.py", line 54, in __call__
    response = upcall(request, *args, **kwargs)
  File "/usr/lib/python3/dist-packages/django/views/decorators/vary.py", line 21, in inner_func
    response = func(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/piston3/resource.py", line 229, in __call__
    else: stream = srl.render(request)
  File "/usr/lib/python3/dist-packages/piston3/emitters.py", line 464, in render
    response = serializers.serialize(format, self.data, indent=True)
  File "/usr/lib/python3/dist-packages/django/core/serializers/__init__.py", line 129, in serialize
    s.serialize(queryset, **options)
  File "/usr/lib/python3/dist-packages/django/core/serializers/base.py", line 52, in serialize
    for obj in queryset:
TypeError: 'Node' object is not iterable

====================

+ curl --fail --data-urlencode op=new --data-urlencode autodetect_nodegroup=1 --data-urlencode hostname=192-168-9-83.cluster.maas --data-urlencode architecture=amd64 --data-urlencode subarchitecture=generic --data-urlencode power_type= --data-urlencode power_parameters= --data-urlencode mac_addresses=00:25:90:4c:f0:28 --data-urlencode mac_addresses=00:25:90:4c:f0:29 http://192.168.9.2/MAAS/api/1.0/nodes/
  % Total % Received % Xferd Average Speed Time Time Time Current
                                 Dload Upload Total Spent Left Speed
100 221 0 0 100 221 0 787 --:--:-- --:--:-- --:--:-- 786
curl: (22) The requested URL returned error: 500 INTERNAL SERVER ERROR