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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _tscube_app(self, xmlfile):
 """Run gttscube as an application."""


        xmlfile = self.get_model_path(xmlfile)

        outfile = os.path.join(self.config['fileio']['workdir'],
                               'tscube%s.fits' % (self.config['file_suffix']))

        kw = dict(cmap=self.files['ccube'],
                  expcube=self.files['ltcube'],
                  bexpmap=self.files['bexpmap'],
                  irfs=self.config['gtlike']['irfs'],
                  evtype=self.config['selection']['evtype'],
                  srcmdl=xmlfile,
                  nxpix=self.npix, nypix=self.npix,
                  binsz=self.config['binning']['binsz'],
                  xref=float(self.roi.skydir.ra.deg),
                  yref=float(self.roi.skydir.dec.deg),
                  proj=self.config['binning']['proj'],
                  stlevel=0,
                  coordsys=self.config['binning']['coordsys'],
                  outfile=outfile)

        run_gtapp('gttscube', self.logger, kw)