@property
  def absent_key_allowed(self):
    return self.__absent_key_allowed
extend with value checking
dataset/ETHPy150Open GoogleCloudPlatform/python-compat-runtime/appengine-compat/exported_appengine_sdk/google/appengine/datastore/cloud_datastore_validator.py/_ValidationConstraint.absent_key_allowed--crossover with--dataset/ETHPy150Open correl/Transmission-XBMC/resources/lib/basictypes/rlist.py/rlist.extend