Setup of our TODO project

Let’s first create a proper environment to work in. I’ll be using Visual Studio Code for this project, and I suggest you do the same. If you want to use something else, that’s fine too. I won’t use anything that specifically requires VSCode, it’s just to make life easier.

Step 1: Create a directory

Let’s first create a directory to work in. If you followed Python Fundamental I, you might still have the project on your computer. Feel free to reuse that.

I called my working directory todo-app. Put it anywhere you like to put your projects. I usually use a short path like C:\dev\todo-app, because I hate constantly entering and looking at giant path names in my terminal and such. I do the same on Mac or Linux, and I usually have a folder called dev in my home directory. The path would then be ~/dev/todo-app. Nice and short!

Step 2: Fire up VSCode

Now it’s time to start VSCode. As you may know by now, I like the command line and usually open a shell and start VSCode with the code command inside the project directory. But you can just as well open VS Code, go File -> Open folder and select the folder.

Step 3: Create the todo.py script

Now you might still have this file from the previous course, in which case you can skip this step. Otherwise, create a file called todo.py and paste the TODO app code into it:

exit = False

todo_items = []


def get_argument(command):
    command_name, argument = command.split(" ", maxsplit=1)
    return argument


def handle_add_command(command):
    task = get_argument(command)
    print(f"Adding task: {task}")
    todo_items.append(task)


def handle_delete_command(command):
    item_number = get_argument(command)
    print(f"Deleting task: {item_number}")
    todo_items.pop(int(item_number) - 1)


def handle_list_command():
    index = 0
    for todo_item in todo_items:
        index += 1
        print(f"{index}. {todo_item}")


def handle_open_command(command):
    # Read a list of todo items from a file, one per line
    filename = get_argument(command)
    filename += ".todo.txt"

    with open(filename, "r") as file:
        for line in file:
            todo_items.append(line.strip())


def handle_save_command(command):
    # Save the list to a file, one item per line
    filename = get_argument(command)
    filename += ".todo.txt"
    with open(filename, "w") as file:
        for todo_item in todo_items:
            file.write(f"{todo_item}\n")


def process_command(command):
    exit = False

    if command.startswith("exit"):
        exit = True
    elif command.startswith("add"):
        handle_add_command(command)
    elif command.startswith("delete"):
        handle_delete_command(command)
    elif command.startswith("list"):
        handle_list_command()
    elif command.startswith("open"):
        handle_open_command(command)
    elif command.startswith("save"):
        handle_save_command(command)
    else:
        print("Command not recognized")

    return exit


while not exit:
    command = input("Enter command: ")
    exit = process_command(command)

Make sure to test if the script works as-is by starting it with python todo.py. You should get an input prompt asking for a command to be entered.