Class SMTPServerDisconnected

              object --+            
                       |            
exceptions.BaseException --+        
                           |        
        exceptions.Exception --+    
                               |    
                   SMTPException --+
                                   |
                                  SMTPServerDisconnected

Not connected to any SMTP server.

This exception is raised when the server unexpectedly disconnects, or when an attempt is made to use the SMTP instance before connecting it to a server.