Can these sides make a triangle?

You will write the triangle inequality as code, find the limits for a third side, and list the whole numbers that fit.

The idea. Three lengths make a triangle when the longest is less than the sum of the other two. If two sides are $a$ and $b$, the third side $c$ must satisfy $|a - b| < c < a + b$.

Your tasks.

1. In can_form, return True when the three lengths make a triangle.
2. In third_side_limits, return the pair (low, high) with low = |a - b| and high = a + b.
3. In whole_numbers, return the list of whole numbers that the third side can be.