This is the code can somebody find the problem?

todos = []

while True:
    user_action = input("Type add ,show, complete, edit or exit: ")
    user_action = user_action.strip()

    match user_action:
        case 'add':
            todo = input("Enter a todo: ") + "\n" ur backslash was a normal slash

            file = open('todos.txt', 'r')
            todos = file.readlines()
            file.close()

            todos.append(todo)

            file = open('todos.txt', 'w')
            file.writelines(todos)
            file.close()
        case 'show':
            for index, item in enumerate(todos):
                row = f"{index+1}-{item}"
                print(row)
            print(len(todos))
        case 'edit':
            number = int(input("Number of the todo to edit: "))
            number = number - 1
            new_todo = input("Enter a new todo: ")
            todos[number] = new_todo
        case 'complete':
            number = int(input("Number of the todo to complete: "))
            todos.pop(number)
        case 'exit':
            break

print("Bye...")