def create_single_method(self, estimator_index, estimator):
        """
        Port a method for a single tree.

        Parameters
        ----------
        :param estimator_index : int
            The estimator index.
        :param estimator : RandomForestClassifier
            The estimator.

        Returns
        -------
        :return : string
            The created method.
        """
        indices = [str(e) for e in estimator.tree_.feature]

        tree_branches = self.create_branches(
            estimator.tree_.children_left, estimator.tree_.children_right,
            estimator.tree_.threshold, estimator.tree_.value, indices, 0, 1)

        temp_single_method = self.temp('embedded.single_method')
        return temp_single_method.format(method_name=self.method_name,
                                         method_id=str(estimator_index),
                                         n_classes=self.n_classes,
                                         tree_branches=tree_branches)