replace a key in a Map variable at a specific index.
The map type of dart does not allow to retrieve an index. Consequently I decided to remove the index but also retrieve the position of the Key where I removed the key. Then, I converted the Map into a list type. Then, I inserted the new Key at the recorded index. Then, I converted the List into a Map. Tada.
I used a class for a reason. The list is made of object. Every object has a Key and a value. Thus the constructor is Construction(Key, Value) Every item of the list are of the form (Construction(key,Value);