DOC : add note + linter guard

tacaswell · tacaswell · commit 96d37e369043 · 2015-02-27T08:29:00.000-05:00
diff --git a/lib/matplotlib/_pylab_helpers.py b/lib/matplotlib/_pylab_helpers.py
@@ -84,7 +84,9 @@ def destroy_fig(cls, fig):
 
     @classmethod
     def destroy_all(cls):
-        import gc
+        # this is need to ensure that gc is available in corner cases
+        # where modules are being torn down after install with easy_install
+        import gc  # nnqa
         for manager in list(cls.figs.values()):
             manager.canvas.mpl_disconnect(manager._cidgcf)
             manager.destroy()
