First you create implementations inside DataStorageImpl.
I “forgot” to remove one implementation this might help you get started.

After implementations are done you can do the following exercises from the Exercises class.
You need to define the lambda expressions cleverly to succeed.

1. Find everyone that has firstName: “Erik” using findMany().
2. Find all females in the collection using findMany().
3. Find all who are born after (and including) 2000-01-01 using findMany().
4. Find the Person that has an id of 123 using findOne().
5. Find the Person that has an id of 456 and convert to String with following content:
   “Name: Nisse Nilsson born 1999-09-09”. Use findOneAndMapToString().
6. Find all male people whose names start with “E” and convert each to a String using findManyAndMapEachToString().
7. Find all people who are below age of 10 and convert them to a String like this:
   “Olle Svensson 9 years”. Use findManyAndMapEachToString() method.
8. Using findAndDo() print out all people with firstName “Ulf”.
9. Using findAndDo() print out everyone who have their lastName contain their firstName.
10. Using findAndDo() print out the firstName and lastName of everyone whose firstName is a palindrome.
11. Using findAndSort() find everyone whose firstName starts with A sorted by birthdate.
12. Using findAndSort() find everyone born before 1950 sorted reversed by lastest to earliest.
13. Using findAndSort() find everyone sorted in following order: lastName > firstName > birthdate.