Hello, I have a file `_core.pyd` that comes from [QGIS](http://www.qgis.org) installation (file enclosed) that I can't use with stubgen: ``` Critical error during semantic analysis: mypy: can't decode file '_core.pyd': 'utf-8' codec can't decode byte 0x90 in position 2: invalid start byte ``` [_core.zip](https://github.com/python/mypy/files/3905454/_core.zip)