Backport PR #18026: FIX: Be sure matplotlib.backends is imported before we use it

timhoffm · meeseeksmachine · commit 25fe49a4fd8b · 2020-07-23T11:03:07.000Z
diff --git a/lib/matplotlib/pyplot.py b/lib/matplotlib/pyplot.py
@@ -227,7 +227,8 @@ def switch_backend(newbackend):
         The name of the backend to use.
     """
     global _backend_mod
-
+    # make sure the init is pulled up so we can assign to it later
+    import matplotlib.backends
     close("all")
 
     if newbackend is rcsetup._auto_backend_sentinel:
