Addition/Multiplication Quiz Generator Python

def perform_test():
    '''The function begins with a welcome message. Then prompts the user to
    input integers for two things:
    1) What operation the user would like to be tested on
    (0 for addition and 1 for multiplcation)
    2) The number of questions they would like to receive

    The test will then produce n questions in the chosen operation.
    If the user answers a question correctly, proceed to the next question.
    If the question is answered incorrectly, inform the user that it is
    incorrect and tell them the correct answer.

    After the test, the results are printed as follows:
    If the final score is >=80%: Excellent work!
    If final score is 60 <= g <= 80: Not bad but you should study more.
    If final score is < 60: You need to practice more'''

    import random
    print('Welcome to the Addition/Multiplication Test!')
    print('Which operation would you like to be tested on?')
    #Prompts user to select operation and number of questions
    test_type = int(input('Input 0 for addition and 1 for multiplication: '))

#ADDITION TEST
    if test_type == 0:
        n=int(input('Enter the number of questions for the test: '))
        if n==0:
            print('Goodbye')
            exit()
        #Created a total_q variable to serve as a calculation of the
        #overall grade as n will be subtracted by 1 with each new question
        #'correct' is a variable that will increase by 1 with each right answer
        total_q = n
        correct = 0

        #This part will repeatedly display questions until n=0
        while n > 0:
            a=random.randint(0,9)
            b=random.randint(0,9)
            n=n-1
            s=a+b
            print(a,'+',b)
            q=int(input('What is the answer?: '))
            if q == s:
                correct = correct + 1
            else:
                print('Incorrect. The answer is',s,'.')

        if n == 0:
            #grade is the score received after taking the test
            grade = (correct / total_q)*100
        if grade >= 80:
            print('Your grade is',grade,'. Nice work!')
        elif 60 <= grade < 80:
            print('Your grade is',grade,'. Not bad but a little more studying would help.')
        elif grade < 60:
            print('Your grade is',grade,'. You need to study more. Ask your teacher for help.')

#MULTIPLICATION TEST
    if test_type == 1:
        n=int(input('Enter the number of questions for the test: '))
        if n==0:
            print('Goodbye')
            exit()
        #Created a total_q variable to serve as a calculation of the
        #overall grade as n will be subtracted by 1 with each new question
        #'correct' is a variable that will increase by 1 with each right answer
        total_q = n
        correct = 0

        #This part will repeatedly display questions until n=0
        while n > 0:
            a=random.randint(0,9)
            b=random.randint(0,9)
            n=n-1
            p=a*b
            print(a,'*',b)
            q=int(input('What is the answer?: '))
            if q == p:
                correct = correct + 1
            else:
                print('Incorrect. The answer is',p,'.')

        if n == 0:
            #grade is the score received after taking the test
            grade = (correct / total_q)*100
        if grade >= 80:
            print('Your grade is',grade,'. Nice work!')
        elif 60 <= grade < 80:
            print('Your grade is',grade,'. Not bad but a little more studying would help.')
        elif grade < 60:
            print('Your grade is',grade,'. You need to study more. Ask your teacher for help.')