/usr/include/ is in libpythia8-dev 8.1.86-1.2.
This file is owned by root:root, with mode 0o755.
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/usr/include/Pythia8/
/usr/include/Pythia8/Pythia8/
/usr/include/Pythia8/Pythia8/SigmaEW.h
/usr/include/Pythia8/Pythia8/Pythia.h
/usr/include/Pythia8/Pythia8/PhaseSpace.h
/usr/include/Pythia8/Pythia8/MergingHooks.h
/usr/include/Pythia8/Pythia8/SLHAinterface.h
/usr/include/Pythia8/Pythia8/ParticleData.h
/usr/include/Pythia8/Pythia8/HelicityBasics.h
/usr/include/Pythia8/Pythia8/RHadrons.h
/usr/include/Pythia8/Pythia8/ParticleDecays.h
/usr/include/Pythia8/Pythia8/SpaceShower.h
/usr/include/Pythia8/Pythia8/PythiaComplex.h
/usr/include/Pythia8/Pythia8/ResonanceWidths.h
/usr/include/Pythia8/Pythia8/ProcessContainer.h
/usr/include/Pythia8/Pythia8/SigmaExtraDim.h
/usr/include/Pythia8/Pythia8/SusyResonanceWidths.h
/usr/include/Pythia8/Pythia8/Settings.h
/usr/include/Pythia8/Pythia8/HadronScatter.h
/usr/include/Pythia8/Pythia8/SusyLesHouches.h
/usr/include/Pythia8/Pythia8/SigmaLeptoquark.h
/usr/include/Pythia8/Pythia8/SusyCouplings.h
/usr/include/Pythia8/Pythia8/TauDecays.h
/usr/include/Pythia8/Pythia8/WeakShowerMEs.h
/usr/include/Pythia8/Pythia8/FastJet3.h
/usr/include/Pythia8/Pythia8/BeamParticle.h
/usr/include/Pythia8/Pythia8/SigmaLeftRightSym.h
/usr/include/Pythia8/Pythia8/SigmaHiggs.h
/usr/include/Pythia8/Pythia8/LesHouches.h
/usr/include/Pythia8/Pythia8/Info.h
/usr/include/Pythia8/Pythia8/History.h
/usr/include/Pythia8/Pythia8/SigmaQCD.h
/usr/include/Pythia8/Pythia8/PartonLevel.h
/usr/include/Pythia8/Pythia8/PythiaStdlib.h
/usr/include/Pythia8/Pythia8/StringFragmentation.h
/usr/include/Pythia8/Pythia8/BoseEinstein.h
/usr/include/Pythia8/Pythia8/StandardModel.h
/usr/include/Pythia8/Pythia8/HelicityMatrixElements.h
/usr/include/Pythia8/Pythia8/HiddenValleyFragmentation.h
/usr/include/Pythia8/Pythia8/FragmentationSystems.h
/usr/include/Pythia8/Pythia8/TimeShower.h
/usr/include/Pythia8/Pythia8/SigmaSUSY.h
/usr/include/Pythia8/Pythia8/Event.h
/usr/include/Pythia8/Pythia8/SigmaProcess.h
/usr/include/Pythia8/Pythia8/Merging.h
/usr/include/Pythia8/Pythia8/Analysis.h
/usr/include/Pythia8/Pythia8/LHAPDFInterface.h
/usr/include/Pythia8/Pythia8/MiniStringFragmentation.h
/usr/include/Pythia8/Pythia8/MultipartonInteractions.h
/usr/include/Pythia8/Pythia8/FragmentationFlavZpT.h
/usr/include/Pythia8/Pythia8/UserHooks.h
/usr/include/Pythia8/Pythia8/Basics.h
/usr/include/Pythia8/Pythia8/PartonDistributions.h
/usr/include/Pythia8/Pythia8/ProcessLevel.h
/usr/include/Pythia8/Pythia8/SigmaCompositeness.h
/usr/include/Pythia8/Pythia8/FJcore.h
/usr/include/Pythia8/Pythia8/LHAFortran.h
/usr/include/Pythia8/Pythia8/HadronLevel.h
/usr/include/Pythia8/Pythia8/PartonSystems.h
/usr/include/Pythia8/Pythia8/BeamShape.h
/usr/include/Pythia8/Pythia8/SigmaGeneric.h
/usr/include/Pythia8/Pythia8/SigmaTotal.h
/usr/include/Pythia8/Pythia8/SigmaOnia.h
/usr/include/Pythia8/Pythia8/SigmaNewGaugeBosons.h
/usr/include/Pythia8/Pythia8/BeamRemnants.h
/usr/include/Pythia8/Pythia8/ResonanceDecays.h
/usr/include/Pythia8/Pythia8/Pythia8ToHepMC.h
/usr/include/pythia8