fix import

dcherian · dcherian · commit 54bea40afe48 · 2019-12-07T13:49:41.000-07:00
diff --git a/xarray/core/nanops.py b/xarray/core/nanops.py
@@ -9,6 +9,7 @@
     from . import dask_array_compat
 except ImportError:
     dask_array = None
+    dask_array_compat = None  # type: ignore
 
 
 def _replace_nan(a, val):
