def __missing__(self, key):
        if self.default_factory is None:
            raise KeyError(key)
        else:
            ret = self[key] = self.default_factory(name=key)
            return ret
def residual_with_slice_fn(inp, out):
      inp_sliced = array_ops.slice(inp, [0, 0], [-1, 3])
      return inp_sliced + out