keras/src/layers/preprocessing/text_vectorization.py/TextVectorization/compute_output_shape
class TextVectorization:    def compute_output_shape(self, input_shape):
        if self._output_mode == "int":
            return (input_shape[0], self._output_sequence_length)
        if self._split is None:
            if len(input_shape) <= 1:
                input_shape = tuple(input_shape) + (1,)
        else:
            input_shape = tuple(input_shape) + (None,)
        return self._lookup_layer.compute_output_shape(input_shape)