Since the annotations are processed just like all other expressions in the symbol table, the generated entries for functions etc. This would result with 

def foo():
    for number in range(5):
        foo: (yield number)
    return number

foo()

returning a generator / coroutine (depending on yield/yield from/await usage). Is this something we want to keep or maybe tweak the symbol table generator to not to handle annotations (since there are also more subtle issues regarding analysis of cell / free vars).