Class UnknownPropertyException

                                                object --+                
                                                         |                
                                  exceptions.BaseException --+            
                                                             |            
                                          exceptions.Exception --+        
                                                                 |        
             exception.device_atlas_exception.DeviceAtlasException --+    
                                                                     |    
exception.invalid_property_name_exception.InvalidPropertyNameException --+
                                                                         |
                                                                        UnknownPropertyException

The UnknownPropertyException is thrown by the Api class when there is an attempt to fetch a property that is unknown for the supplied User-Agent or tree.