(self, labels: Iterable[Dict], **kwargs)
Override this method to provide label merging support.

        :param labels:          A collection of labels.
        :return:                The merged label, or None to skip merging of the current label.
Override this method to provide label merging support.
Override this method to provide label merging support .
def _merge_labels(self, labels: Iterable[Dict], **kwargs) -> Optional[Dict]:
        """
        Override this method to provide label merging support.

        :param labels:          A collection of labels.
        :return:                The merged label, or None to skip merging of the current label.
        """
        raise NotImplementedError()
def _merge_labels ( self , labels : Iterable [ Dict ] , * * kwargs ) -> Optional [ Dict ] : raise NotImplementedError ( )