(ndb.Model):     prop_a = ndb.StringProperty()     prop_b = ndb.StringProperty()     prop_c = ndb.StringProperty()      @ndb.tasklet     def some_method_0(self):         self.prop_a = "The result of some computation"         yield self.put_async()      @ndb.tasklet     def some_method_0(self):         if some_condition:             self.prop_b = "Some new value"             yield self.put_async()      @ndb.tasklet     def some_method_0(self):         if some_condition:             self.prop_b = "Some new value"             yield self.put_async()      