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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 _discarded_reads2_out_file_name(self):
 """Checks if file name is set for discarded reads2 output. Returns absolute path."""

        if self.Parameters['-4'].isOn():
            discarded_reads2 = self._absolute(str(self.Parameters['-4'].Value))
        else:
            raise ValueError(
                "No discarded-reads2 (flag -4) output path specified")
        return discarded_reads2