Kata

Make your own product function

• The product function multiplies all the elements in iterable given as the first argument and returns the product.
• There will be a second argument (optional, default: 1) to specify the start element to multiply.
• When the iterable is empty, returns the start element.

For example:

product()  # 1
product([1, 2, 3])  # 1 * 2 * 3
product([1, 2, 3], -1)  # -1 * 1 * 2 * 3