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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 _check_vpcs_version(self):
 """ Checks if the VPCS executable version is >= 0.8b or == 0.6.1. """

        try:
            output = yield from subprocess_check_output(self._vpcs_path(), "-v", cwd=self.working_dir)
            match = re.search("Welcome to Virtual PC Simulator, version ([0-9a-z\.]+)", output)
            if match:
                version = match.group(1)
                self._vpcs_version = parse_version(version)
                if self._vpcs_version < parse_version("0.6.1"):
                    raise VPCSError("VPCS executable version must be >= 0.6.1 but not a 0.8")
            else:
                raise VPCSError("Could not determine the VPCS version for {}".format(self._vpcs_path()))
        except (OSError, subprocess.SubprocessError) as e:
            raise VPCSError("Error while looking for the VPCS version: {}".format(e))