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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 _format_output(self, outfile_name, out_type):
 """ Prepend proper output prefix to output filename """


        outfile_name = self._absolute(outfile_name)
        outparts = outfile_name.split("/")
        outparts[-1] = self._out_format % (out_type, outparts[-1] )

        return '/'.join(outparts)