Merge pull request #6519 from paulromano/writeraw-fix

Fix FigureCanvasAgg.print_raw(...)

lib/matplotlib/backends/backend_agg.py

@@ -509,7 +509,7 @@ def print_raw(self, filename_or_obj, *args, **kwargs):
             fileobj.write(renderer._renderer.buffer_rgba())
         finally:
             if close:
-                filename_or_obj.close()
+                fileobj.close()
             renderer.dpi = original_dpi
     print_rgba = print_raw