delete(key) {
    const { bucketIndex, entryIndex, keyIndex } = this._getIndexes(key);

    if (entryIndex === undefined) {
      return false;
    }

    this.buckets[bucketIndex].splice(entryIndex, 1);
    delete this.keysArrayWrapper[keyIndex];
    this.size--;

    return true;
  }
Returns true if an element in the Map object existed and has been removed, or false if the element does not exist.
@param {any} key