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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 wait(self):
 """Wait for child process to terminate. Set and return returncode attribute."""

        self._returncode = self.process.wait()
        try:
            self.process.stderr.close()
        except:
            pass
        self.set_status(self.S_DONE, "status set to Done")

        return self._returncode