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/1935#issuecomment-367795719,https://api.github.com/repos/pydata/xarray/issues/1935,367795719,MDEyOklzc3VlQ29tbWVudDM2Nzc5NTcxOQ==,1217238,2018-02-22T19:37:51Z,2018-02-22T19:37:51Z,MEMBER,"It's exciting to see people testing xarray with PyPy! Once we get this working, we should consider adding a continuous integration test.

The specific problem here seems to be `dask.SerializableLock`, which xarray initializes upon import:
https://github.com/dask/dask/blob/de6c2a49d76066abb51085570816322f063fc5c5/dask/utils.py#L737

I think this could be reproduced with something like the following using only the standard library:
```
import weakref
import threading

lock = threading.Lock()

locks = weakref.WeakValueDictionary()
locks['foo'] = lock
```

This works with CPython, but maybe not with pypy.

CC @mrocklin in case he has any ideas. Otherwise if my code to reproduce works, I would suggest reporting this upstream to PyPy.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,299346082