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
188869101,MDU6SXNzdWUxODg4NjkxMDE=,1113,rasm.nc is not a valid NetCDF 3 file,156023,closed,0,,,8,2016-11-11T22:57:01Z,2017-04-29T21:57:13Z,2016-11-11T23:29:25Z,NONE,,,,"Not sure if this is a duplicate of #1106 or something crazy that I'm doing....

I'm attempting to play with the xarray_multidimensional_coords.ipynb but I cant load the sample dataset.
Below are my versions (I just installed xarray using pip today)
('numpy version  : ', '1.11.2')
('pandas version : ', u'0.19.0')
('xarray version   : ', '0.8.2')

Pasting the full trace below


```
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-6-3af9bb5e86b6> in <module>()
----> 1 ds = xr.tutorial.load_dataset('rasm')
      2 ds

/usr/local/lib/python2.7/dist-packages/xarray/tutorial.pyc in load_dataset(name, cache, cache_dir, github_url, **kws)
     53         _urlretrieve(url, localfile)
     54 
---> 55     ds = _open_dataset(localfile, **kws).load()
     56 
     57     if not cache:

/usr/local/lib/python2.7/dist-packages/xarray/backends/api.pyc in open_dataset(filename_or_obj, group, decode_cf, mask_and_scale, decode_times, concat_characters, decode_coords, engine, chunks, lock, drop_variables)
    210                 store = backends.NetCDF4DataStore(filename_or_obj, group=group)
    211             elif engine == 'scipy':
--> 212                 store = backends.ScipyDataStore(filename_or_obj)
    213             elif engine == 'pydap':
    214                 store = backends.PydapDataStore(filename_or_obj)

/usr/local/lib/python2.7/dist-packages/xarray/backends/scipy_.pyc in __init__(self, filename_or_obj, mode, format, group, writer, mmap)
     94             filename_or_obj = BytesIO(filename_or_obj)
     95         self.ds = scipy.io.netcdf_file(
---> 96             filename_or_obj, mode=mode, mmap=mmap, version=version)
     97         super(ScipyDataStore, self).__init__(writer)
     98 

/home/dokeeffe/.local/lib/python2.7/site-packages/scipy/io/netcdf.pyc in __init__(self, filename, mode, mmap, version, maskandscale)
    262 
    263         if mode in 'ra':
--> 264             self._read()
    265 
    266     def __setattr__(self, attr, value):

/home/dokeeffe/.local/lib/python2.7/site-packages/scipy/io/netcdf.pyc in _read(self)
    577         if not magic == b'CDF':
    578             raise TypeError(""Error: %s is not a valid NetCDF 3 file"" %
--> 579                             self.filename)
    580         self.__dict__['version_byte'] = fromstring(self.fp.read(1), '>b')[0]
    581 

TypeError: Error: /home/dokeeffe/.xarray_tutorial_data/rasm.nc is not a valid NetCDF 3 file
```","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/1113/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,completed,13221727,issue