Add a missing self.

QuLogic · QuLogic · commit 6d93441763ce · 2020-03-28T22:13:13.000-04:00
diff --git a/lib/matplotlib/tests/test_agg.py b/lib/matplotlib/tests/test_agg.py
@@ -101,7 +101,7 @@ class BaseFilter:
         def get_pad(self, dpi):
             return 0
 
-        def process_image(padded_src, dpi):
+        def process_image(self, padded_src, dpi):
             raise NotImplementedError("Should be overridden by subclasses")
 
         def __call__(self, im, dpi):
