Trouble figuring out how to pass a value between functions?

[Reta]

Hey all, the following block of code yields a "decide" is not defined

I created a 'decide=input()' inside a function
Is it possible to call 'decide' into a different function?

regPizza = ["Pepperoni", "Hawaiian", "Cheesey Cheese", "Meats' R Us", "Vegatarian"]
premPizza = ["Pepperoni Supreme", "Hawaiian Supreme", "Cheese Supreme", "Meats' R Us Supreme", "Vegatarian Supreme"]
decide = ""
def banner():
    print("-------------------Welcome to Dream Pizzas! Where we care about your money but not you!-------------------")

def pizzaReg():
    print("The following Pizzas all cost $5")
    print(regPizza)
    decide=input("Would you like to view our premium selection of Pizzas? Yes or No")
    return decide


def pizzaPrem(decide):
    if decide == "Yes":
        print("The following  premium Pizzas all cost $13.50")
        print(premPizza)
    elif decide == "No":
        raise SystemExit
    

banner()

pizzaReg()

decide = pizzaPrem()

[Yoriz]

assign the result of pizzaReg() to decide, then pass into pizzaReg()

decide = pizzaReg()
 
pizzaPrem(decide)