code: def _build_command(self):
          
  
          command = [self._path]
          command.extend(["-N1"])  # use instance IDs for filenames
          command.extend(["-l", "dynamips_i{}_log.txt".format(self._id)])  # log file
          # Dynamips cannot listen for hypervisor commands and for console connections on
          # 2 different IP addresses.
          # See https://github.com/GNS3/dynamips/issues/62
          if self._console_host != "0.0.0.0" and self._console_host != "::":
              command.extend(["-H", "{}:{}".format(self._host, self._port)])
          else:
              command.extend(["-H", str(self._port)])
          return command
docs: Command to start the Dynamips hypervisor process.
          (to be passed to subprocess.Popen())