Description

Implement a Multi Set. Like a set, it allows for efficient storage and retrieval of items without a guaranteed order.

However, unlike a set, it allows for multiple occurrences of the same element by tracking the count of each unique element it contains.

Example:

Input: values = "value1", "value2" 
Output: [[{key: "value1", count:2}, {key: "value2", count:1}]]