shorten lines for whatsnew

Jiang Yue · Jiang Yue · commit af35fa32845a · 2019-05-23T09:01:49.000+08:00
diff --git a/doc/source/whatsnew/v0.25.0.rst b/doc/source/whatsnew/v0.25.0.rst
@@ -90,7 +90,8 @@ would be reassigned as -1. (:issue:`19387`)
 
 .. ipython:: python
 
-    mi1 = pd.MultiIndex(levels=[[np.nan, None, pd.NaT, 128, 2]], codes=[[0, -1, 1, 2, 3, 4]])
+    mi1 = pd.MultiIndex(levels=[[np.nan, None, pd.NaT, 128, 2]],
+                        codes=[[0, -1, 1, 2, 3, 4]])
     mi2 = pd.MultiIndex(levels=[[1, 2]], codes=[[0, -2]])
 
 *Previous Behavior*:
