1. Fork and clone this repository.
2. Familiarize yourself with the file structure of this repository.
3. Achieve the following objectives by carefully reading what is being asked and executing.

You are given a file named users.txt. Your goal is to validate that each user's username is unique.

Create a function called validate_file() (in name_checker.py) which accepts a name of a file to validate. This function validates the users.txt file and checks that the first name for each user does not contain any numbers (0123456789). This function raises (throws) a ValidationException object and is consumed in the following manner:

Test Case:

def test():
    try:
        validate_file("users.txt")
    except ValidationException as ve:
        print(ve)

test()

Output:

Invalid first name: 'B1ll'

• This tests your ability to read files, select the correct data, manipulate strings and use Exceptions in python.

GLHF :)