issues: 178887041

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id node_id number title user state locked assignee milestone comments created_at updated_at closed_at author_association active_lock_reason draft pull_request body reactions performed_via_github_app state_reason repo type
178887041 MDU6SXNzdWUxNzg4ODcwNDE= 1016 DataArray coords: tuple vs. list 5497186 closed 0     2 2016-09-23T14:08:15Z 2018-10-31T16:56:47Z 2018-10-31T16:56:47Z NONE      

is there a reason the coords dictionary values cannot be a tuple? I found this fairly baffling to debug when it tripped me up.

```

this works

xarray.DataArray(np.random.random((3, 3, 3)), dims=('one', 'two', 'three'), coords={ 'one': ['four', 'five', 'six'], } )

this throws the following error

ValueError: dimensions ('four',) must have the same length as the number of data dimensions, ndim=0

xarray.DataArray(np.random.random((3, 3, 3)), dims=('one', 'two', 'three'), coords={ 'one': ('four', 'five', 'six'), } ) ```

even if there was a clearer error it would help quite a bit. As it stands you are thinking, 'what?! four isn't a dimension!'

using 0.8.2

 
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