How would I append a students score to their names?

Here I am trying to change my code so that the students last three scores are saved to their names, but at the moment it will just save their scores and when the teacher prints their scores it will just print all the times the student did the quiz regardless of how many times they did it. here is my code:

import random
import sys

def get_input_or_quit(prompt, quit="Q"):
    prompt += " (Press '{}' to exit) : ".format(quit)
    val = input(prompt).strip()
    if val.upper() == quit:
        sys.exit("Goodbye")
    return val

def prompt_bool(prompt):
    while True:
        val = get_input_or_quit(prompt).lower()
        if val == 'yes':
          return True
        elif val == 'no':
          return False
        else:
         print ("Invalid input '{}', please try again".format(val))


def prompt_int_small(prompt='', choices=(1,2)):
    while True:
        val = get_input_or_quit(prompt)
        try:
            val = int(val)
            if choices and val not in choices:
                raise ValueError("{} is not in {}".format(val, choices))
            return val
        except (TypeError, ValueError) as e:
                print(
                    "Not a valid number ({}), please try again".format(e)
                    )

def prompt_int_big(prompt='', choices=(1,2,3)):
    while True:
        val = get_input_or_quit(prompt)
        try:
            val = int(val)
            if choices and val not in choices:
                raise ValueError("{} is not in {}".format(val, choices))
            return val
        except (TypeError, ValueError) as e:
                print(
                    "Not a valid number ({}), please try again".format(e)
                    )

role = prompt_int_small("Are you a teacher or student? Press 1 if you are a student or 2 if you are a teacher")
if role == 1:
    score=0
    name=input("What is your name?")
    print ("Alright",name,"welcome to your maths quiz."
            " Remember to round all answers to 5 decimal places.")
    level_of_difficulty = prompt_int_big("What level of difficulty are you working at?\n"
                                 "Press 1 for low, 2 for intermediate "
                                    "or 3 for high\n")


    if level_of_difficulty == 3:
        ops = ['+', '-', '*', '/']
    else:
        ops = ['+', '-', '*']

    for question_num in range(1, 11):
        if level_of_difficulty == 1:
            max_number = 10
        else:
            max_number = 20

        number_1 = random.randrange(1, max_number)
        number_2 = random.randrange(1, max_number)

        operation = random.choice(ops)
        maths = round(eval(str(number_1) + operation + str(number_2)),5)
        print('\nQuestion number: {}'.format(question_num))
        print ("The question is",number_1,operation,number_2)
        answer = float(input("What is your answer: "))
        if answer == maths:
            print("Correct")
            score = score + 1
        else:
            print ("Incorrect. The actual answer is",maths)

    if score >5:
        print("Well done you scored",score,"out of 10")
    else:
        print("Unfortunately you only scored",score,"out of 10. Better luck next time")

    class_number = prompt_int_big("Before your score is saved ,are you in class 1, 2 or 3? Press the matching number")

    filename = (str(class_number) + "txt")
    with open(filename, 'a') as f:
        f.write("\n" + str(name) + " scored " + str(score) +  " on difficulty level " + str(level_of_difficulty) + "\n")
    with open(filename) as f:
        lines = [line for line in f if line.strip()]
        lines.sort()

    if prompt_bool("Do you wish to view previous results for your class"):
        for line in lines:
            print (line)
    else:
        sys.exit("Thanks for taking part in the quiz, your teacher should discuss your score with you later")
if role == 2:
    class_number = prompt_int_big("Which class' scores would you like to see? Press 1 for class 1, 2 for class 2 or 3 for class 3")
    filename = (str(class_number) + "txt")

    f = open(filename, "r")
    lines = [line for line in f if line.strip()]
    lines.sort()
    for line in lines:
        print (line)