Xelawho: Read his homework description again. The function is supposed to use *AND MODIFY* the global variable fullname. *THAT* is why it is so stupid.
The "framework" that will test his code is not even going to LOOK at the return value from the function. And idiotic framework written, as VIPStephan says, to illustrate the worst possible way to do things. Makes sense to me. NOT.
An optimist sees the glass as half full.
A pessimist sees the glass as half empty.
A realist drinks it no matter how much there is.