prepareWorkerFormulation = (workerName, deferTask) => {
      if (workerName === undefined) {
        return undefined;
      }
      const workerId = petStore.identifyLocal(workerName);
      if (workerId === undefined) {
        deferTask(identifiers =>
          petStore.write(workerName, identifiers.workerId),
        );
      }
      return workerId;
    }
@param {string | undefined} workerName
@param {DeferredTasks<{ workerId: string }>['push']} deferTask