code: public static ModuleIdentifier forFlagValue(String flagValue) {
      if (flagValue.startsWith("goog:")) {
        return ModuleIdentifier.forClosure(flagValue);
      } else {
        return ModuleIdentifier.forFile(flagValue);
      }
    }
docs: Returns an identifier for an --entry_point flag value.
  
  @param flagValue The flag value. If it is in one of the formats `goog:name.space` or
  `goog:moduleName:name.space`, it is interpreted as a Closure namespace. Otherwise, it is
  interpreted as the path to an ES or CommonJS module.