diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index af3e24aff9d5..603adab4f0f0 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -11756,6 +11756,10 @@ let
     # package, apparently some kind of plugin.
     doCheck = false;
 
+    prePatch = optionalString isPyPy ''
+      grep -rl 'utf-8-with-signature-unix' ./ | xargs sed -i -e "s|utf-8-with-signature-unix|utf-8|g"
+    '';
+
     meta = {
       description = "Pyutil, a collection of mature utilities for Python programmers";