text: let INSTANCE = null;
  
  function getManager() {
    if (!INSTANCE) {
      throw new Error('Manager instance must be initialised first.');
    }
  
    return INSTANCE;
  }
  
  function initManager({
    manager: Manager,
    ...config
  }) {
    if (!INSTANCE) {
      INSTANCE = new Manager({
        ...config,
      });
    }
  
    return INSTANCE;
  }
  
  module.exports = {
    getManager,
    initManager,
  };
  