Mortgage Calculator For Python

#beggining
def start():
    start1 = True

    start2 = input("Hello, and welcome to your Mortgage Calculator. Please Enter \"Start\" to start")
    if start2.upper() == "START":
        print("Starting...")
    else:
        print("You have not written \"Start\"")
        start1 = False

    if start2.upper() == "START":
        print("Hello, in order to begin, we need to know the cost of each payment, wether the payment is monthly, weekly, or daily, and we need to know the interest rate")


    #questions
    Amount = float(input("How much of a loan have you taken?"))
    interest_rate = float(input("What is the interest rate on the loan? Please input the interest as a decimal. \n For example, a 3 percent interest rate would be written like 0.03"))
    payment_method = input("Is the payment monthly, yearly, or weekly?")
    if payment_method.lower() == "monthly":
        month = int(input("How many months do you have to play the loan off in?"))
    if payment_method.lower() == "yearly":
        year = int(input("How many Years do you have to play the loan off in?"))
    if payment_method.lower()== "weekly":
        week = int(input("How many months do you have to play the loan off in?"))
    else:
        print("Please check to make sure that you have written \"Monthly\", \"Yearly\", or \"Weekly\" correctly.")



    interest_total = (Amount * interest_rate) + Amount

    if payment_method.lower() == "monthly":
        a = interest_total / month
        print("You are going to have to pay {} per month".format(a))
    if payment_method.lower() == "yearly":
        b = interest_total / year
        print("You are going to have to pay {} per year".format(b))
    if payment_method.lower()== "weekly":
        c = interest_total / week
        print("You are going to have to pay {} per week".format(c))

def start2():
    Amount = float(input("How much of a loan have you taken?"))
    interest_rate = float(input("What is the interest rate on the loan? Please input the interest as a decimal. \n For example, a 3 percent interest rate would be written like 0.03"))
    payment_method = input("Is the payment monthly, yearly, or weekly?")
    if payment_method.lower() == "monthly":
        month = int(input("How many months do you have to play the loan off in?"))
    if payment_method.lower() == "yearly":
        year = int(input("How many Years do you have to play the loan off in?"))
    if payment_method.lower()== "weekly":
        week = int(input("How many months do you have to play the loan off in?"))
    else:
        print("Please check to make sure that you have written \"Monthly\", \"Yearly\", or \"Weekly\" correctly.")



    interest_total = (Amount * interest_rate) + Amount

    if payment_method.lower() == "monthly":
        a = interest_total / month
        print("You are going to have to pay {} per month".format(a))
    if payment_method.lower() == "yearly":
        b = interest_total / year
        print("You are going to have to pay {} per year".format(b))
    if payment_method.lower()== "weekly":
        c = interest_total / week
        print("You are going to have to pay {} per week".format(c))

def restart():
    restart = input("If you would like to restart, please type \"Start\"")
    if restart.upper() == "START":
        start2()

start()
restart()