Traceback for index.yaml bug

Traceback (most recent call last):

  ...

  File "/base/python_lib/versions/1/google/appengine/ext/db/__init__.py", line 1585, in fetch
    raw = raw_query.Get(limit, offset)
  File "/base/python_lib/versions/1/google/appengine/api/datastore.py", line 1079, in Get
    prefetch_count=limit)._Get(limit)
  File "/base/python_lib/versions/1/google/appengine/api/datastore.py", line 1021, in _Run
    str(exc) + '\nThis query needs this index:\n' + yaml)
NeedIndexError: no matching index found.
This query needs this index:
- kind: _AppEngineUtilities_Cache
  properties:
  - name: cachekey
  - name: timeout