You will develop a bash script to manage users. The script will take three script arguments: an input filename of users, a group name, and an operation flag.

The input filename of users to manage will be a text file with a list of users to add to the system or remove from the system. Each line in the file will contain a User ID and an encrypted password, which are separated by a space character as a delimiter. Your input user file should have at least five users. You will need to encrypt your passwords via the command line using openssl and place the generated password in your input user file.

Write a script that adds and removes users to a Linux system using the input file provided to the script. The users should be added to group provided in the script argument. You will want to check if the group already exists. Use an operation of -a to signify to add the users to the system and an operation of -r to signify removing the users from the system. When adding users, make sure you create the user's home directory. When you remove the user, make sure to delete the user's home directory. Your script should check that the proper number of script arguments are given, check for empty and blank lines from the input file, and provide feedback to the user while the script is executing.