Generate the next neural architecture.

        Returns
        -------
        other_info: any object
            Anything to be saved in the training queue together with the architecture.
        generated_graph: Graph
            An instance of Graph.

def generate(self):
        """Generate the next neural architecture.

        Returns
        -------
        other_info: any object
            Anything to be saved in the training queue together with the architecture.
        generated_graph: Graph
            An instance of Graph.
        """
        generated_graph, new_father_id = self.bo.generate(self.descriptors)
        if new_father_id is None:
            new_father_id = 0
            generated_graph = self.generators[0](
                self.n_classes, self.input_shape
            ).generate(self.default_model_len, self.default_model_width)

        return new_father_id, generated_graph