diff --git a/gnu/packages/machine-learning.scm b/gnu/packages/machine-learning.scm
index 25a22b076f..4e18cf0517 100644
--- a/gnu/packages/machine-learning.scm
+++ b/gnu/packages/machine-learning.scm
@@ -2827,6 +2827,7 @@ (define-public python-pytorch
 
        ;; XXX: Tests attempt to download data such as
        ;; <https://raw.githubusercontent.com/pytorch/test-infra/master/stats/slow-tests.json>.
+       ;; We're also missing some Python modules, such as expecttest.
        #:tests? #f))
     (native-inputs
      `(("cmake" ,cmake)