def format_h5_backtrace(self, backtrace=None):
        if backtrace is None:
            backtrace = self.h5backtrace

        if backtrace is None:
            return 'No HDF5 back trace available'
        else:
            return ''.join(traceback.format_list(backtrace))


# Initialize the policy for HDF5 back trace handling
Returns longest path of all possible paths between a list of nodes.
dataset/ETHPy150Open PyTables/PyTables/tables/exceptions.py/HDF5ExtError.format_h5_backtrace--crossover with--dataset/ETHPy150Open ungarj/label_centerlines/src_create_centerlines.py/get_longest_paths