#NEWLINE# def __setattr__( self , name , value ) : #NEWLINE# #INDENT# if ( self . _mutable or ( value == '_mutable' ) ) : #NEWLINE# #INDENT# object . __setattr__ ( self , name , value ) #NEWLINE# #UNINDENT# else : #NEWLINE# #INDENT# raise TypeError ( "Can't modify immutable instance" )