#NEWLINE# def message( self , msg = None ) : #NEWLINE# #INDENT# '\n        Queue msg on stack message queue\n        ' #NEWLINE# if ( msg is not None ) : #NEWLINE# #INDENT# self . tx = self #NEWLINE# #UNINDENT# if ( self . tx is None ) : #NEWLINE# #INDENT# raise ValueError ( '{0}: {1} Cannot message. No .tx.\n' . format ( self . stack . name , self . name ) ) #NEWLINE# #UNINDENT# self . stack . message ( self . tx , self . device )