Question

Create a python script to manage a user list that can be modified and saved to a text file.

Input text file consisting of pairs of usernames and passwords, separated by a colon (:) without any spaces

User choice: (‘n’-new user account, ‘e’-edit existing user account, ‘d’- delete existing user account, ‘l’- list user accounts, ‘q’-quit)

List of user accounts, error messages when appropriate

Output text file consisting of pairs of username and passwords, separated by a colon (:) without any spaces

The program maintains a list of user accounts and passwords supplied by a system administrator.

Any inputted username should be stripped of any non-alphanumeric characters (special characters such as ! @ # $ % ^ & * ( ) _ + ; : ’ ”) using: username = re.sub(r'\W+','',username) [You need to import the library "re"] and should be converted to lowercase: username = username.lower()

Any inputted password should be stripped of the apostrophe character ' using: password = password.replace('\'', '')

Each option should be implemented as a separate function within a Package that will be imported, so that its functions can be called. Valid options will be stored in a list to test for invalid options:
function = [‘n’, ‘e’, ‘d’, ‘l’, ‘q’]

The usernames and passwords will be loaded from an input file and stored in a dictionary (Python’s version of a hash). The dictionary will be passed as a parameter from the Python script file to the appropriate function in the module file and updated according to the function. The script file should import the functions from the module file to call the appropriate function.

Initially, the program prompts for an input text file to read from. If the file does not exist, it should be created. The program should then loop until the user chooses to quit (selects status as ‘q’). If the user enters an illegal status, the program will prompt again for the status input. Upon quitting, the program prompts the user to save the list to an output file with the same name as the original input text file.

Sample output:

Enter file to open: myfile.txt

User accounts
-------------
n = New user account
e = Edit existing user account
d = Delete existing user account
l = List user accounts
q = Quit

Enter choice: n
Enter username: einstein
Enter password: e=mc^2

User accounts
-------------
n = New user account
e = Edit existing user account
d = Delete existing user account
l = List user accounts
q = Quit

Enter choice: n
Enter username: newton
Enter password: f=ma

User accounts
-------------
n = New user account
e = Edit existing user account
d = Delete existing user account
l = List user accounts
q = Quit

Enter choice: n
Enter username: pythagoras
Enter password: a^2+b^2=c^2

User accounts
-------------
n = New user account
e = Edit existing user account
d = Delete existing user account
l = List user accounts
q = Quit

Enter choice: n
Enter username: einstein
Username already exists!

User accounts
-------------
n = New user account
e = Edit existing user account
d = Delete existing user account
l = List user accounts
q = Quit

Enter choice: e
Enter username to modify: fibonacci
Username does not exist!

User accounts
-------------
n = New user account
e = Edit existing user account
d = Delete existing user account
l = List user accounts
q = Quit

Enter choice: e
Enter username to edit: newton
Enter current password: f=m*a
Incorrect password!

User accounts
-------------
n = New user account
e = Edit existing user account
d = Delete existing user account
l = List user accounts
q = Quit

Enter choice: e
Enter username to edit: newton
Enter current password: f=ma
Enter new password: force=mass*accelaration

User accounts
-------------
n = New user account
e = Edit existing user account
d = Delete existing user account
l = List user accounts
q = Quit

Enter choice: d
Enter username to delete: pythagoras
User removed

User accounts
-------------
n = New user account
e = Edit existing user account
d = Delete existing user account
l = List user accounts
q = Quit

Enter choice: l
einstein:e=mc^2
newton:force=mass*accelaration

User accounts
-------------
n = New user account
e = Edit existing user account
d = Delete existing user account
l = List user accounts
q = Quit

Enter choice: q
Save contents? (y/n): y
% more myfile.txt
einstein:e=mc^2
newton:force=mass*acceleration