text: 
  import { extendObservable, action } from 'mobx';
  
  function counterStoreBuilder() {
    extendObservable(this, {
      counter: 0,
      list: [],
  
      inc: action((arg) => {
        console.log(arg);
        this.counter++
      }),
  
      dec: action(() => {
        this.counter--
      }),
  
      addList: action(() => {
        this.list.push({ text: 'Added List' })
      }),
  
      removeList: action(() => {
        this.list.splice(this.list.length - 1, 1)
      }),
  
    })
  }
  
  const counterStore = new counterStoreBuilder()
  
  export default counterStore
  