No because as I said this is highly unlikely. You are basically looking for an input (seed variable) that could produce a SHA256 hash that is between N and 2²⁵⁶ and that range is very small in comparison to 1 to N range.

What you could do for this test is to split the "create_key_pair" method into two parts, one computes the hash and the other creates the key pair. Now you can feed any hash result you want to the second method like 2²⁵⁶ and see how it fails.