Print GOEA results to the screen or to a file.

def prt_results(self, goea_results):
        """Print GOEA results to the screen or to a file."""
        # objaart = self.prepgrp.get_objaart(goea_results) if self.prepgrp is not None else None
        if self.args.outfile is None:
            self._prt_results(goea_results)
        else:
            # Users can print to both tab-separated file and xlsx file in one run.
            outfiles = self.args.outfile.split(",")
            grpwr = self.prepgrp.get_objgrpwr(goea_results) if self.prepgrp else None
            if grpwr is None:
                self.prt_outfiles_flat(goea_results, outfiles)
            else:
                grpwr.prt_outfiles_grouped(outfiles)