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