Apply a price change

Write set_price(prices, item, price) that stores price under item in the dictionary you are given, adding the item if it is new or replacing the old price, and returns that same dictionary. Do not build a new one.

set_price({"apple": 40}, "bread", 25)  ->  {"apple": 40, "bread": 25}
set_price({"apple": 40}, "apple", 45)  ->  {"apple": 45}

def set_price(prices, item, price):
    ...