Problem in appending histogram to a list


I am trying to append a few histograms to a list. But the code is not working for more than one element. Can anyone please help me to point out the problem?

import ROOT as r
histsig = []
variable ='InvariantMass_of_4_particle_with_totCharge==0_in_tau1iso_tau2iso'
sigtitle = ['RSGraviton','BulkGraviton','Radion','nonreco','SM']
color = [2,4,6,8,12]
for ifile in range(0,4) :
    file_ = r.TFile(filesig[ifile])
    print ifile, '****************',histsig
print histsig

it seems the name of histogram is not accessible after few iteration

0 **************** [<ROOT.TH1F object ("RSGraviton") at 0x3bb27f0>]
1 **************** [<ROOT.TH1F object ("BulkGraviton") at 0x3bb27f0>, <ROOT.TH1F object ("BulkGraviton") at 0x3bb27f0>]

 *** Break *** segmentation violation
2 **************** [

There was a crash.
This is the entire stack trace of all threads:

Please help me

Do you really believe that this is different from Problem in adding histograms to root ? I’d suggest we look at Problem in adding histograms to root first, and if the issue here then still exists we can revisit it.

In general there is no need to open two topics for the same problem…