Michael Niklas

> (FYI I had been the mypy person here — for my sins — but I think this is beyond my understanding — so putting an issue into mypy might...

See https://github.com/pydata/xarray/issues/6726#issuecomment-1257279640. We are thinking in doing the backend imports only when needed.

I would like to have a "ignore" option as well, such that I can do `input_core_dims=[["x","y"]]` in your example.

How about inheriting from FileNotFoundError, this Exception type would be the first guess of people. And while at it, you could inherit from ValueError to keep it backwards compatible.

What exactly do you mean by netcdf attributes? The special meaning ones like units, _FillValue or long_name? In general xarray is quite relaxed on what users put into the attrs,...

> I might have thought both of them could be encapsulated in a single func... Maybe that's `infix_dims`, or fine to rename! I always thought that these two methods are...

> Yes! `...` is the better synonym — `None` is somewhat an artifact of history. So +1 for `replace_none`, which maybe we can gradually turn to `False` by default over...

I think it is best to implement two functions, one for sets of dims and one for sequences of dims. This will be easier to type/read/use than trying to put...

> I performed doctests on my machine inside a conda venv following the [Contributing Guide](https://docs.xarray.dev/en/stable/contributing.html#creating-a-development-environment) using Python 3.9, and passed the them. > > Yet, it doesn't pass the github...

> Any ideas about how to avoid this issue on Windows? I have not figured that out. Usually the difference is small enough to fix it by hand. Maybe we...