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/2148#issuecomment-540187230,https://api.github.com/repos/pydata/xarray/issues/2148,540187230,MDEyOklzc3VlQ29tbWVudDU0MDE4NzIzMA==,2448579,2019-10-09T20:45:58Z,2019-10-09T20:45:58Z,MEMBER,"Everything but this last example works as expected

```
arr = xr.DataArray(
    np.ones((5, 2)), 
    dims=('x', 'y'), 
    coords={
        'x': ('x', np.array([1, 1, 1, 2, 2])),
        'x1': ('x', np.array([1, 1, 1, 2, 2])),
        'x2': ('x', np.array([1, 2, 3, 4, 5])),
    }
)

arr.groupby(xr.DataArray([1,1,1,2,2], dims=('x'), name='y')).mean('x')

<xarray.DataArray (y: 4)>
array([1., 1., 1., 1.])
Coordinates:
  * y        (y) int64 1 2

```","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,324032926