Write a function that, when passed a list and a target sum, returns, **efficiently** with respect to time used, two distinct** **zero-based indices of any two of the numbers, whose sum is equal to the target sum. If there are no two numbers, the function should return *None*.

For example, *find_two_sum([3, 1, 5, 7, 5, 9], 10)* should return a single *tuple* containing any of the following pairs of indices:

- 0 and 3 (or 3 and 0) as 3 + 7 = 10
- 1 and 5 (or 5 and 1) as 1 + 9 = 10
- 2 and 4 (or 4 and 2) as 5 + 5 = 10

- Example case: Wrong answer
- Distinct numbers with and without solutions: Wrong answer
- Duplicate numbers with and without solutions: Wrong answer
- Performance test with a large list of numbers: Wrong answer

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