text: from google.cloud import ndb
  
  
  class SimpleModel(ndb.Model):
      str_prop = ndb.StringProperty()
      int_prop = ndb.IntegerProperty()
  
  
  class ChildModel(ndb.Model):
      str_prop = ndb.StringProperty()
  
  
  class RepeatedPropertyModel(ndb.Model):
      int_props = ndb.IntegerProperty(repeated=True)
  
  
  class KeyPropertyModel(ndb.Model):
      model_ref = ndb.KeyProperty(kind=SimpleModel)
  