we don't need no steengkeeng asserts

This, works. The asserts fail because the datetime stamp is not being received by them in a format they are happy with. That is a syntax or perhaps a coding standards issue that I believe falls outside of the scope of the original tasking, which was to report on the number of working hours between two datetime stamps. 

I consider it a lesson on the dangers of relying on test-driven development, the code cannot succeed if the tests are flawed even though code can fail even if it passes the tests. Case in point, the first assert contains an error, there's only 7 working hours between 1 pm Thursday and noon on Friday.