// This is required to populate derived attributes during export in a
  // meaningful way. Else during export to GraphDef element_type() query
  // will result in out of bounds access/assert.
  if (handle_dtype().getSubtypes().size() != 1) {
    return emitOpError(
        "must have exactly one subtype in the result variant type");
  }

  if (!IsOfRankOrUnranked(op.getElementShape(), 0) &&