Your cousin, anna hannah banana, has a massive song collection. she is also a wealthy entrepreneur. she wants a better way to manage her music and thinks other people want the same thing. she has convinced you join her and her start a company that will sell a simple system that will allow her, and all your future customers, to build a song managment tool that allows users to add, delete, and list their songs in their collections.

Implement a document scanning function wordcountengine, which receives a string document and returns a list of all unique words in it and their number of occurrences, sorted by the number of occurrences in a descending order. if two or more words have the same count, they should be sorted according to their order in the original sentence. assume that all letters are in english alphabet. you function should be case-insensitive, so for instance, the words “perfect” and “perfect” should be considered the same word.