def __iter__(self):
    for o in self._pre_outputs:
        if isinstance(o, string_types):
            ds = self._load(o, **self.kwargs)
            self._setup_function(ds)
            (yield ds)
        else:
            (yield o)
def __iter__(self):
    for o in self._pre_outputs:
        if isinstance(o, string_types):
            ds = self._load(o, **self.kwargs)
            self._setup_function(ds)
            (yield ds)
        else:
            (yield o)