code: def get_instance(target_type, **kwargs):
          
          if target_type in TARGET_TYPES:
              cls = TARGET_TYPES[target_type]
              try:
                  return cls(**kwargs)
              except Exception:
                  logger.error("Please make sure that you picked the correct target type: "
                               "--target-type CLI option.")
                  raise
  
          raise ColinException(
              "Unknown target type '{}'. Please make sure that you picked the correct target type: "
              "--target-type CLI option.".format(target_type))
docs: :param target_type: string, either image, dockertar, ostree or dockerfile