var obj0 = {'a': 'testA1', 'b': 'testB1'}
var obj1 = {'a': 'testA2', 'b': 'testB2'}
var obj2 = {'a': 'testA3', 'b': 'testB3'}

var obj01 = {'0': {0: obj0, 1: obj1, 2: obj2,}}

function print(a) {
  console.log(a)
}

// console.log(obj.length) // undefined

var num = 0
var toStringResult = num.toString();
console.log(toStringResult); // 0

var obj01_h0 = obj01.toStringResult
console.log(obj01_h0); // undefined

// err
// console.log(Object.keys(obj01.0.toString().length))
// console.log(Object.keys(obj01_h0.length))

// if(obj.indexOf('testA') !== -1) {
//   console.log(obj.length)
// }