[2020/04/27 21:09:53.860] ======================================================================
 [2020/04/27 21:09:53.860] FAIL [0.033s]: test_index_filter (test_collection.TestCollection)
 [2020/04/27 21:09:53.860] ----------------------------------------------------------------------
 [2020/04/27 21:09:53.860] Traceback (most recent call last):
 [2020/04/27 21:09:53.860]   File "/data/mci/e02cdbd4d09c5ecb23ef3468a44c35dc/src/test/__init__.py", line 447, in wrap
 [2020/04/27 21:09:53.860]     return f(*args, **kwargs)
 [2020/04/27 21:09:53.860]   File "/data/mci/e02cdbd4d09c5ecb23ef3468a44c35dc/src/test/test_collection.py", line 626, in test_index_filter
 [2020/04/27 21:09:53.860]     {"x": {"$exists": True}}]})
 [2020/04/27 21:09:53.860] AssertionError: OperationFailure not raised