Class MaestroNotAvailableError

              object --+                
                       |                
exceptions.BaseException --+            
                           |            
        exceptions.Exception --+        
                               |        
        exceptions.StandardError --+    
                                   |    
              exceptions.ImportError --+
                                       |
                                      MaestroNotAvailableError

Error class to indicate that Maestro is not available and there was an attempt to use it.