Consider the form provided here. The form should validate all fields once the "Create user" button is clicked and it should clear the form if validation has passed.

The fields have the following constraints:

First name - required, must have at least one character that is not a whitespace.
Last name - required, must have at least one character that is not a whitespace.
Username - required.
Description - no constraints.
Address - no constraints.
Address 2 - optional, if provided it should have at most 5 characters.
Age - optional, if provided it should be a number between 18 and 65, both included.
Password - required, it should have at least 4 characters.

Test the form and select all the fields that were not implemented correctly.