Simple nickname authentication

[alsehendo34]

I would like a very simple file based unencrypted nickname authentication capability--not even password and without any registration.

When the user submits to:
Please enter your nickname
I would just like it to check a list in a file I have hand entered and ask again if not in there.
I am not a programmer @ all.
This is secure enough for me--I would just handout nicknames to my friends and family.

nickname_file.txt
Bob
Steve
Blue
Mary