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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 update_default_iou_values(self):
 """ Finds the default RAM and NVRAM values for the IOU image. """


        try:
            output = yield from gns3server.utils.asyncio.subprocess_check_output(self._path, "-h", cwd=self.working_dir, stderr=True)
            match = re.search("-n <n>\s+Size of nvram in Kb \(default ([0-9]+)KB\)", output)
            if match:
                self.nvram = int(match.group(1))
            match = re.search("-m <n>\s+Megabytes of router memory \(default ([0-9]+)MB\)", output)
            if match:
                self.ram = int(match.group(1))
        except (ValueError, OSError, subprocess.SubprocessError) as e:
            log.warning("could not find default RAM and NVRAM values for {}: {}".format(os.path.basename(self._path), e))