#!/usr/bin/env python
# coding=utf-8

import ROOT

f = ROOT.TFile("hist.root")

h = f.Get("hist")



x = ROOT.RooRealVar("x","x",2.75,3.07)

data = ROOT.RooDataHist("data","dataset with x",ROOT.RooArgList(x),h)

pdf = ROOT.RooHistPdf("pdf","pdf",ROOT.RooArgSet(x),data)

frame = x.frame()
pdf.plotOn(frame,ROOT.RooFit.DrawOption("FL"),ROOT.RooFit.FillColor(ROOT.kRed))

frame.Draw()