html_url,issue_url,id,node_id,user,created_at,updated_at,author_association,body,reactions,performed_via_github_app,issue
https://github.com/pydata/xarray/issues/1366#issuecomment-471766745,https://api.github.com/repos/pydata/xarray/issues/1366,471766745,MDEyOklzc3VlQ29tbWVudDQ3MTc2Njc0NQ==,1217238,2019-03-11T22:34:17Z,2019-03-11T22:34:17Z,MEMBER,This will be eventually fixed as part of https://github.com/pydata/xarray/issues/1603,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,220533356
https://github.com/pydata/xarray/issues/1366#issuecomment-292847045,https://api.github.com/repos/pydata/xarray/issues/1366,292847045,MDEyOklzc3VlQ29tbWVudDI5Mjg0NzA0NQ==,1217238,2017-04-10T04:27:02Z,2017-04-10T04:27:02Z,MEMBER,"This is a little tricky: there's only a single array `Variable` object (the MultiIndex), so we can't save `attrs` on any of the levels. But xarray doesn't raise an error in this case, because it's assigning to the temporary `mda['band']` object, which immediately gets thrown away. There would be the same issue if you tried to assign an attribute to `ds['time.dayofyear']`.

I don't think Python syntax gives us any good options for identifying these cases. It's essentially the same problem as assigning to an indexing result, e.g., `ds.sel(...).attrs = ...`, though it's less obvious here since you're doing indexing, not a method call.

At the very least we could document that this doesn't work.

CC @benbovy in case he has any other ideas.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,220533356