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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 _restart_target(self):
 """ Restart our Target. """

        if self._server:
            if self._server.returncode is None:
                self._server.kill()
                time.sleep(0.2)
        self._server = subprocess.Popen("python session_server.py", stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True)
        time.sleep(0.2)