#include "GeneratorInterface/GenFilters/interface/PythiaFilterGammaGamma.h"
#include "DataFormats/Math/interface/LorentzVector.h"
#include "Math/GenVector/VectorUtil.h"
#include "SimDataFormats/GeneratorProducts/interface/HepMCProduct.h"
#include "TFile.h"
#include "TLorentzVector.h"
#include <iostream>