To answer your other question, no, strview isn't related - that's strictly a PEP 3118 *consumer*, which is well supported from the Python side now that memoryview is fixed.

The trick will be to allow a Python implemented object to be a PEP 3118 exporter *without* having to inherit from a C implemented type that does the slot mapping. Since PEP 3118 didn't describe a Python level API for the protocol, it may actually require a new PEP.

One example for what you could do with it: use the new memoryview.cast() to provide multidimensional views on an exporter that only supports 1D exports natively.