diff --git a/doc/mock_modules.txt b/doc/mock_modules.txt
index 38fdb590ebef74e0591616bc1613787fbe78cc0e..8004b2a20cb994326fddbd334e1f3d206357397b 100644
--- a/doc/mock_modules.txt
+++ b/doc/mock_modules.txt
@@ -1,3 +1,4 @@
+deprecation
 nibabel
 nibabel.fileslice
 numpy