Vending Machine

Program Requirements

1. Insert coins

• Write a function called insert_coin which takes two arguments: one called coin and another called inserted_coins.

• The coin parameter will accept the values any of the following values: 5, 10, 25, 100, 200. These values represents cents. Any other value should raise a ValueError exception.

• The "inserted_coins" parameter is a list

• When the function insert_coin() is called, the "coin" value is appended to the insert_coins parameter.

2. Buy a product

• Write a function called buy_product which takes two arguments: one called "product" and the other is called "balance".

• The product argument may be one of the following values: "drink", "candy", "chips". Any other value should raise a ValueError exception.

• balance is an integer representing the current balance of funds available

• When the buy_product function is called, the price of the chosen product is compared to the balance.

• If the balance of the inserted coins is less than the cost of the product, a custom exception called InsufficientFunds should be raised.

• If the balance equals or exceeds the cost of the product, then the function will return the balance minus the cost of the purchased product.

• The product costs are:

  • Drink: $2.75
  • Chips: $2.25
  • Candy: $3.15

3. Return change

• Write a function called return_change which takes a single argument called "balance".

• If the balance is greater than zero, return a list of coins (can be any combination of 5, 10, 25, 100, 200) which will sum up to the balance.

• If for whatever reason the balance is not a multiple of 5, then the sum of coins returned should be rounded down to the nearest multiple of 5, and not exceed the balance.

• The coins returned should be the largest first, then the smallest.