TYP:  IndexEngine.get_indexer_with_fill
pandas/core/indexes/base.py:3696: error: "IndexEngine" has no attribute "get_indexer_with_fill"  [attr-defined]

Is this code intended to be reached only by certain sub-classes of `IndexEngine` that have `get_indexer_with_fill`?

I'm not sure how this is related to `cache_readonly = property` but it was found that way.