diff --git a/pkgs/development/python-modules/graphene/default.nix b/pkgs/development/python-modules/graphene/default.nix
index c6508cef7a7..8e556fdd7c5 100644
--- a/pkgs/development/python-modules/graphene/default.nix
+++ b/pkgs/development/python-modules/graphene/default.nix
@@ -5,6 +5,7 @@
 , graphql-core
 , graphql-relay
 , promise
+, py
 , pytest-asyncio
 , pytest-benchmark
 , pytest-mock
@@ -37,6 +38,7 @@ buildPythonPackage rec {
 
   checkInputs = [
     promise
+    py
     pytestCheckHook
     pytest-asyncio
     pytest-benchmark