I am attempting to create a loop which a user can stop at the end of the program. I've tried various solutions, none of which have worked, all I have managed to do is create the loop but I can't seem to end it. I only recently started learning Python and I would be grateful if someone could enlighten me on this issue.

```
def main():
 while True:
    NoChild = int(0)
    NoAdult = int(0)
    NoDays  = int(0)
    AdultCost = int(0)
    ChildCost = int(0)
    FinalCost = int(0)

    print ("Welcome to Superslides!")
    print ("The theme park with the biggest water slide in Europe.")

    NoAdult = int(raw_input("How many adults are there?"))
    NoChild = int(raw_input("How many children are there?"))
    NoDays  = int(raw_input("How many days will you be at the theme park?"))
    WeekDay = (raw_input("Will you be attending the park on a weekday? (Yes/No)"))

    if WeekDay == "Yes":
        AdultCost = NoAdult * 5

    elif WeekDay == "No":
        AdultCost = NoAdult * 10

    ChildCost = NoChild * 5

    FinalCost = (AdultCost + ChildCost)*NoDays

    print ("Order Summary")
    print("Number of Adults: ",NoAdult,"Cost: ",AdultCost)
    print("Number of Children: ",NoChild,"Cost: ",ChildCost)
    print("Your final total is:",FinalCost)
    print("Have a nice day at SuperSlides!")

    again = raw_input("Would you like to process another customer? (Yes/No)")
    if again =="No":
        print("Goodbye!")
        return
    elif again =="Yes":
        print("Next Customer.")

    else:
        print("You should enter either Yes or No.")

if __name__=="__main__":
main()

```