Before we look at the implementation, let’s review the interface provided by the map ADT. You will notice that this interface is very similar to the Python dictionary.
Map() Create a new, empty map.put(key,val) Add a new key-value pair to the map. If the key is already in the map then replace the old value with the new value.get(key) Given a key, return the value stored in the map or None otherwise.del Delete the key-value pair from the map using a statement of the form del map[key].len() Return the number of key-value pairs stored in the map.in Return True for a statement of the form key in map, if the given key is in the map.