diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index 40f57d9ebbf8..d2e5474786b6 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -8214,7 +8214,7 @@ let
       sha256 = "bec9269cbfa58de4f0849ec79bb7d54eeeed9df8b5fbfa1637fbc68062822847";
     };
 
-    buildInputs = with self; [ pbr pip ];
+    buildInputs = with self; [ pbr pip ] ++ optional isPy26 argparse;
 
     propagatedBuildInputs = with self; [ setuptools ];