'Decrement rows larger than the given row.'

def shift_left(self, row):

    if self.unique:
        for (key, x) in self.data.items():
            if (x > row):
                self.data[key] = (x - 1)
    else:
        for (key, node) in self.data.items():
            self.data[key] = [((x - 1) if (x > row) else x) for x in node]
