def __new__(cls, *items, dmapper=None, rmapper=None):
    obj = super(Schedule, cls).__new__(cls, items)
    obj.dmapper = (dmapper or {})
    obj.rmapper = (rmapper or {})
    return obj
def __new__(cls, *items, dmapper=None, rmapper=None):
    obj = super(Schedule, cls).__new__(cls, items)
    obj.dmapper = (dmapper or {})
    obj.rmapper = (rmapper or {})
    return obj