利用for循环同步执行异步方法

//定义一个异步函数
const foo1 = (i) => {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      console.log(I)
      resolve(i)
    }, 3000)

  })
}
const arr = [1, 2, 3, 4, 5]
async function a() {
  for (var i = 0; i < arr.length; i++) {
    await foo1(arr[i])
  }
}
a()