def add_level(self, irrad, level, add=True):
    p = self.get_level_path(irrad, level)
    lv = dict(z=0, positions=[])
    dvc_dump(lv, p)
    if add:
        self.add(p, commit=False)
def add_level(self, irrad, level, add=True):
    p = self.get_level_path(irrad, level)
    lv = dict(z=0, positions=[])
    dvc_dump(lv, p)
    if add:
        self.add(p, commit=False)