Programming Puzzles: Python Edition

Task

Define a function find_zero_sum_triplets that takes one parameter:

Name	Type	Example Input
input_nums	list of int	[1, 2, 3, 4, 5, -9]

When called, the function should return all possible combinations of the indexes of three numbers that add up to 0. The function should return a list of tuples, each tuple containing the three indexes of the numbers that add up to 0, or an empty list if no such combination exists. The function should be able to deal with duplicate numbers in the input list.