crash: "ValueError: need more than 0 values to unpack"

while testing https://github.com/openmicroscopy/omero-web-docker/pull/26
went to URL: http://localhost:14080/mapr/api/anyvalue/annotations/
crashed with:

Traceback (most recent call last):

  File "/opt/omero/web/venv/lib/python2.7/site-packages/django/core/handlers/base.py", line 132, in get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)

  File "/opt/omero/web/OMERO.web/lib/python/omeroweb/decorators.py", line 486, in wrapped
    retval = f(request, *args, **kwargs)

  File "/opt/omero/web/venv/lib/python2.7/site-packages/omero_mapr/views.py", line 571, in api_annotations
    mapann_value=mapann_value)

ValueError: need more than 0 values to unpack

<WSGIRequest
path:/mapr/api/anyvalue/annotations/,
GET:<QueryDict: {}>,
POST:<QueryDict: {}>,
COOKIES:{'_ga': 'GA1.1.41429663.1534845885',
 'csrftoken': 'SZk5uXlkzUuu5RglihNtEDzKKrDMcm1S',
 'sessionid': 'd4xcgie02du4ok7dkmgbq68v845xphlc'},
META:{u'CSRF_COOKIE': u'SZk5uXlkzUuu5RglihNtEDzKKrDMcm1S',
 'HTTP_ACCEPT': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8',
 'HTTP_ACCEPT_ENCODING': 'gzip, deflate, br',
 'HTTP_ACCEPT_LANGUAGE': 'en-US,en;q=0.9,de;q=0.8',
 'HTTP_CONNECTION': 'keep-alive',
 'HTTP_COOKIE': 'csrftoken=SZk5uXlkzUuu5RglihNtEDzKKrDMcm1S; _ga=GA1.1.41429663.1534845885; sessionid=d4xcgie02du4ok7dkmgbq68v845xphlc',
 'HTTP_DNT': '1',
 'HTTP_HOST': 'localhost:14080',
 'HTTP_UPGRADE_INSECURE_REQUESTS': '1',
 'HTTP_USER_AGENT': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.110 Safari/537.36',
 'PATH_INFO': u'/mapr/api/anyvalue/annotations/',
 'QUERY_STRING': '',
 'RAW_URI': '/mapr/api/anyvalue/annotations/',
 'REMOTE_ADDR': '172.27.0.1',
 'REMOTE_PORT': '38288',
 'REQUEST_METHOD': 'GET',
 'SCRIPT_NAME': u'',
 'SERVER_NAME': '0.0.0.0',
 'SERVER_PORT': '4080',
 'SERVER_PROTOCOL': 'HTTP/1.1',
 'SERVER_SOFTWARE': 'gunicorn/19.9.0',
 'gunicorn.socket': <socket._socketobject object at 0x7f5820a62fa0>,
 'wsgi.errors': <gunicorn.http.wsgi.WSGIErrorsWrapper object at 0x7f5820911cd0>,
 'wsgi.file_wrapper': <class 'gunicorn.http.wsgi.FileWrapper'>,
 'wsgi.input': <gunicorn.http.body.Body object at 0x7f5820911690>,
 'wsgi.multiprocess': True,
 'wsgi.multithread': False,
 'wsgi.run_once': False,
 'wsgi.url_scheme': 'http',
 'wsgi.version': (1, 0)}>

ome / omero-mapr

crash: "ValueError: need more than 0 values to unpack" #42