"The shape that will be returned from print method resembles a diamond ..."

Like others here I spent a ton of time displaying the diamonds in the diamond function instead of returning a string that has the appropriate amount of whitespace and new line returns so the shape can be manufactured by the calling routine.

For me, the instructions are not clear enough for beginners learning python.

Nevermind I just realized it's every number below the number being passed in.

Need clarification on sending solution(10). The expected result is 23 and I'm not sure why.

10 % 3 = 3 6 9 -> 18
10 % 5 = 5 10 -> 15

18+15 = 33 not 23. Result only makes sense if 10 isn't factored in as a multiple of 5. What am I missing?

Well, the examples given in the descriptions were pretty clear :)

That was it. The function should not return the recursive sum. It should return the final single digit after recursion.

I would suggest keeping this comment visible for clarification purposes or modify the instructions for clarity.

Thx I will take a look and report back with any progress