diff --git a/pkgs/development/python-modules/unified-planning/default.nix b/pkgs/development/python-modules/unified-planning/default.nix
index aa7b822..bfff4d7 100644
--- a/pkgs/development/python-modules/unified-planning/default.nix
+++ b/pkgs/development/python-modules/unified-planning/default.nix
@@ -1,7 +1,6 @@
 { lib
 , python3
 , fetchFromGitHub
-, fetchPypi
 , clingo
 }:
 let
@@ -10,9 +9,9 @@ let
   antlr472-python3-runtime = buildPythonPackage rec {
     pname = "antlr4-python3-runtime";
     version = "v4.7.2";
-    src = fetchPypi {
-      inherit pname version;
-      hash = "sha256-Fozc7I+5FS6EqHym/SYbPVTI9jWPQqs7gTsUpxk7tQs=";
+    src = builtins.fetchTarball {
+      url = "https://files.pythonhosted.org/packages/29/14/8ac135ec7cc9db3f768e2d032776718c6b23f74e63543f0974b4873500b2/antlr4-python3-runtime-4.7.2.tar.gz";
+      sha256 = "0m7axw4fys10da5bwpz39nkdji15z8jka3w11m5dx0ym0lag0qvh";
     };
     meta = with lib; {
       description = "Runtime for ANTLR";