How to use the @phenyl/utils.PhenylRestApiDirectClient function in @phenyl/utils

async handleCustomRequest(encodedHttpRequest: EncodedHttpRequest) {
    try {
      const restApiClient = new PhenylRestApiDirectClient(this.restApiHandler);
      const customResponse = await this.customRequestHandler(
        encodedHttpRequest,
        restApiClient
      );
      return customResponse;
    } catch (err) {
      // TODO: Show error in development environment.
      const body = "Internal Server Error.";
      return createPlainTextResponse(body, 500);
    }
  }
}

public createDirectClient(): PhenylRestApiDirectClient {
    return new PhenylRestApiDirectClient(this);
  }