def _parse_message(self, exc):
        return '%s: %s' % (exc.__class__.__name__, str(exc))
merges part that contain x and part containing y
dataset/ETHPy150Open binarydud/pyres/pyres/failure/base.py/BaseBackend._parse_message--crossover with--dataset/ETHPy150Open jilljenn/tryalgo/tryalgo/kruskal.py/UnionFind.union