diff --git a/selftest.py b/selftest.py
index ed5252c4464..661abcddb74 100755
--- a/selftest.py
+++ b/selftest.py
@@ -139,7 +139,9 @@ def testimage() -> None:
     In 1.1.6, you can use the ImageMath module to do image
     calculations.
 
-    >>> im = ImageMath.eval("float(im + 20)", im=im.convert("L"))
+    >>> im = ImageMath.lambda_eval( \
+      lambda args: args["float"](args["im"] + 20), im=im.convert("L") \
+    )
     >>> im.mode, im.size
     ('F', (128, 128))