Instructions

This HW is focused on creating a login system. There will be a file called login_database.csv that is a CSV file of all the usernames and passwords in our database. Here is an excerpt of the starting database:

username,password
jane,bats
john,cats
jessica,rats

Here we can see that we have three users in the database. We can read this CSV file as a list of dictionaries by using the following code:

with open("login_database.csv", 'r') as f
    list_of_users = list(DictReader(f))

list_of_users now is a list of dictionaries. You can now loop through every user like you would any other list.

Your objective is to create a program that allows users to:

1. Login to the system using their credentials (they will enter their username and password). You will check if its valid.
2. Register a new login (user will create a user name and password)
3. Quit. The program save the any newly registered users into login_database.csv before quitting.

Expected Steps and Requirements (10 pts)

1. Create a function called read_database(). It should read the file login_database.csv as a list of dictionaries (see above) and return it. (2 pts)
2. Create a function called login(list_of_users). It should ask the user for the username and then the password. If the username and password exist in the database return True, else return False. (2 pts)
3. Create a function called register(list_of_users). It should ask the user for a username and password. You should then create a dictionary of this new username and password and append to list_of_users. (2 pts)
4. Create a function called write_database(list_of_users). It should overwrite the existing login_database.csv file with list_of_users. Please see the documentation (2pt)
   1. HINT - Open the file like this, with open(DATABASE_FILE, 'w', newline='') as f:
5. Finish the remaining conditional statements in the main function while loop. You should check the command name and then call the respective functions (2 pts)
6. No syntax or run time errors (1 pt)
7. Modify the register function such that you can not have duplicate user names (1pt).

Example Output

This the running program in VSCodes terminal. If you don't have VSCode setup to use GitBash, you will use Windows Terminal.