#NEWLINE# def __setitem__( self , index , new_field ) : #NEWLINE# #INDENT# field = self . _fields [ index ] #NEWLINE# del self . _field_dict [ field . name ] #NEWLINE# self . _fields [ index ] = new_field #NEWLINE# self . _field_names [ index ] = new_field . name #NEWLINE# self . _field_dict [ new_field . name ] = index