From d5381b2ea9d9263a5993f2a73c2b4bad7eb4a554 Mon Sep 17 00:00:00 2001
From: Huilin Qu <huilin.qu@cern.ch>
Date: Thu, 25 Apr 2024 15:46:14 +0200
Subject: [PATCH] Fix metMCTable in NanoGEN.

---
 PhysicsTools/NanoAOD/python/nanogen_cff.py | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/PhysicsTools/NanoAOD/python/nanogen_cff.py b/PhysicsTools/NanoAOD/python/nanogen_cff.py
index 45a8059ee40f2..f47c9d2ede2ff 100644
--- a/PhysicsTools/NanoAOD/python/nanogen_cff.py
+++ b/PhysicsTools/NanoAOD/python/nanogen_cff.py
@@ -7,6 +7,7 @@
 from PhysicsTools.NanoAOD.genWeightsTable_cfi import *
 from PhysicsTools.NanoAOD.genVertex_cff import *
 from PhysicsTools.NanoAOD.common_cff import Var,CandVars
+from PhysicsTools.NanoAOD.simpleSingletonCandidateFlatTableProducer_cfi import simpleSingletonCandidateFlatTableProducer
 
 nanoMetadata = cms.EDProducer("UniqueStringProducer",
     strings = cms.PSet(
@@ -81,8 +82,12 @@ def customizeNanoGENFromMini(process):
     return process
 
 def customizeNanoGEN(process):
-    process.metMCTable.src = "genMetTrue"
-    process.metMCTable.variables = cms.PSet(PTVars)
+    process.metMCTable = simpleSingletonCandidateFlatTableProducer.clone(
+        src = "genMetTrue",
+        name = process.metMCTable.name,
+        doc = process.metMCTable.doc,
+        variables = cms.PSet(PTVars)
+    )
 
     process.rivetProducerHTXS.HepMCCollection = "generatorSmeared"
     process.genParticleTable.src = "genParticles"