Unless I can **really** help it, I try minimise the number of `return` statements to be a single statement at the end of the method/function rather than allow multiple exit points (which reminds me of my Commodore64 GOTO days) :wink: 

How about just setting `structure = None` here ... ? We're not in a loop, it reads better (particularly since the following statement is another `return`) and it shouldn't be than much of a performance hit ...