Simple Python Based Login System

This is a basic command-line program where users can sign up and log in. I made this to practice Python, saving data to files (CSV), and checking user input.

What It Does

• Sign Up: Create a new username and password.
• Log In: Enter your details to get into the system.
• Save Data: It saves user information safely in a data.csv file.
• Check Rules: It makes sure usernames only use lowercase letters and passwords are long enough.

How to Run It

1. Download or clone this code to your computer.

2. Open your terminal (like your Linux/Ubuntu terminal) and go to the project folder.

3. Run this command:

   python3 main.py