def g1(e):
    yield 1
    raise e

def g2():
    yield 1

def append_error(e):
    it = g1(e)
    
    while 1:
        try:
            value = next(it)
        except RuntimeError as e:
            it = g2()
            next(it)
        except StopIteration:
            return

def main():
    append_error(RuntimeError("These exception objects are prepended"))
    append_error(RuntimeError("to the stack of chained errors"))

    raise ValueError("HAI WORLD")

if __name__ == '__main__':
    main()