javascript 배열 중복 제거

(https://stackoverflow.com/questions/2218999/remove-duplicates-from-an-array-of-objects-in-javascript)

var arr=[
{"JANQTY":"49","STD_ITM_NM":"연결송수구명판" ,"EBGTAMT":"1" },
{"JANQTY":"38","STD_ITM_NM":"하론소화기"   , "EBGTAMT":"0"},
{"JANQTY":"49","STD_ITM_NM":"연결송수구명판" ,"EBGTAMT":"0" },
{"JANQTY":"15","STD_ITM_NM":"압력스위치"   ,"EBGTAMT":"0" },
{"JANQTY":"49","STD_ITM_NM":"연결송수구명판" ,"EBGTAMT":"1" }
];


console.log('BEFORE @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ :', arr);

console.log('BEFORE @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ :', JSON.stringify(arr));


arr = [...new Map(arr.map(obj => [JSON.stringify(obj), obj])).values()];


console.log('AFTER  @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ :', arr);

console.log('AFTER  @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ :', JSON.stringify(arr));

/*

Details:-

1. Doing .map() on the data list and converting each individual object into a [key, value] pair array(length =2), the first element(key) would be the stringified version of the object and second(value) would be an object itself.
2. Adding above created array list to new Map() would have the key as stringified object and any same key addition would result in overriding the already existing key.
3. Using .values() would give MapIterator with all values in a Map (obj in our case)
4. Finally, spread ... operator to give new Array with values from the above step.

*/