Create a Map Data Structure clear fail

Tell us what’s happening:
I have changed clear method to

this.collection = {};
``` but still receive the same result

> The clear method empties the map and the size method returns the number of items present in the map.

**Your code so far**

```js

var Map = function() {
  this.collection = {};
  // change code below this line
  this.add = (key,value) => {
        this.collection[key] = value;
    }
    this.remove = (key) => {
        this.collection[key] = undefined;
    }
    this.get = (key) => {
        return this.collection[key];
    }
    this.has = (key) => {
        return this.collection.hasOwnProperty(key);
    }
    this.values = () => {
        return Object.values(this.collection);
    }
    this.size = () => {
        return this.values().length;
    }
    this.clear = () => {
        for(let item of Object.keys(this.collection)) {
            delete this.collection[item];
        }
    }
  // change code above this line
};

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Link to the challenge:
https://learn.freecodecamp.org/coding-interview-prep/data-structures/create-a-map-data-structure

The problem is in your remove method. Use delete there.
I know it said your clear method was wrong but the test is giving a false report.

You’re right.Thank you Tom.