mypy

9d10a3e6 - Inferencing type reference of abstract class inferred from concrete type values (#8096)

Inferencing type reference of abstract class inferred from concrete type values (#8096) Resolves #8050, following the purposed solution 2 in https://github.com/python/mypy/issues/8050#issuecomment-560322273 and using the implementation purposed in https://github.com/python/mypy/issues/8050#issuecomment-560326219