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diff --git a/tools/codegen/core/gen_load_balancing_proto.sh b/tools/codegen/core/gen_load_balancing_proto.sh
index 6d974ce..fb6a468 100755
--- a/tools/codegen/core/gen_load_balancing_proto.sh
+++ b/tools/codegen/core/gen_load_balancing_proto.sh
@@ -110,6 +110,8 @@
 . $VENV_NAME/bin/activate
 popd
 
+# this should be the same version as the submodule we compile against
+# ideally we'd update this as a template to ensure that
 pip install protobuf==3.0.0b2
 
 pushd "$(dirname $1)" > /dev/null