diff --git a/xarray/core/nanops.py b/xarray/core/nanops.py
index fe8b2e784a7..94676e9dda2 100644
--- a/xarray/core/nanops.py
+++ b/xarray/core/nanops.py
@@ -24,7 +24,6 @@ def _replace_nan(a, val):
     return where_method(val, mask, a), mask
 
 
-
 def _maybe_null_out(result, axis, mask, min_count=1):
     """
     xarray version of pandas.core.nanops._maybe_null_out
@@ -106,7 +105,7 @@ def nansum(a, axis=None, dtype=None, out=None, min_count=None):
         result = xp.sum(a, axis=axis, dtype=dtype)
     else:
         mask = isnull(a)
-        result = np.nansum(a, axis=axis, dtype=dtype)      
+        result = np.nansum(a, axis=axis, dtype=dtype)
     if min_count is not None:
         return _maybe_null_out(result, axis, mask, min_count)
     else: