@staticmethod
def transform_to_leaf(topic_model):
    """
        Transforms TopicModel to a leaf for the tree for further integration in the tree.

        Parameters
        ----------
        topic_model : TopicModel
            topic model

        Returns
        -------
        dict
            leaf of the tree

        """
    leaf = {'model_id': topic_model.model_id, 'models': []}
    return leaf
