start = input("Would you like to begin yes/no?")
while start not in ("yes"):
    print("You must enter yes to continue.")
    start = input("Would you like to begin yes/no?")
    while start == "yes":
        while start not in ("yes"):
            start = input("Would you like to begin yes/no?")

            condition = ("True")
            while condition == ("True"):
                import time
                import random

                def countdown(count):
                    while (count >= 0):
                        print ('The count is: ', count)
                        count -= 1
                        time.sleep(1)

                countdown(random.randint(3, 7))
                starter = time.time()
                input("Go")
                ender = time.time()
                print (ender - starter)


                if input("Would you like to input again?") == "no":
                    condition = False