def _parse_op_label(self, label):
        """
        Parses the fields in a node timeline label.
        Copy from tensorflow.timeline
        """
        # Expects labels of the form: name = op(arg, arg, ...).
        match = re.match(r'(.*) = (.*)\((.*)\)', label)
        if match is None:
            return 'unknown', 'unknown', []
        nn, op, inputs = match.groups()
        if not inputs:
            inputs = []
        else:
            inputs = inputs.split(', ')
        return nn, op, inputs

        Parses the fields in a node timeline label.
        Copy from tensorflow.timeline
        
fedlearner/trainer/run_hooks.py