def append_val(self, key, val):
        # If a key doesn't exist, leveldb will throw KeyError
        try:
            current = self.deserialize(self.storage.Get(key))
        except __HOLE__:
            current = []

        # update new list
        current.append( val)
        self.storage.Put(key, self.serialize(current))
dataset/ETHPy150Open brandonrobertz/SparseLSH/sparselsh/storage.py/LevelDBStorage.append_val