elif choice == "A":
    def add_task(count):
        with open ( 'user.txt' ) as fin:
            usernames = [ i.split ( ',' ) [ 0 ] for i in fin.readlines ( ) if len ( i ) > 3 ]
            task = input ( "Please enter the username of the person the task is assigned to.\n" )
        while task not in usernames:
            task = input ( "Username not registered. Please enter a valid username.\n" )
        else:
            task_title = input ( "Please enter the title of the task.\n" )
            task_description = input ( "Please enter the task description.\n" )
            task_due = input ( "Please input the due date of the task. (yyyy-mm-dd)\n" )
            date = datetime.date.today ( )
            task_completed = False
            if task_completed == False:
                task_completed = "No"
            else:
                task_completed = ("Yes")
            with open ( 'tasks.txt' , 'a+' ) as task1:
                count = count + 1
                task1.write ( "\n User assigned to task: " , str (
                    count ) + "\n" + task + "\nTask Title :" + "\n" + task_title + "\n" + "Task Description:\n" + task_description + "\n" + "Task Due Date:\n" + str (
                    task_due ) + "\n" + "Date Assigned:\n" + str (
                    date ) + "\n" + "Task Completed:\n" + task_completed + "\n" )
                file.close ( )
                print ( "The new assigned task has been saved" )
    count = 0
    add_task ( count )

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