def configure_listener(mapper, class_):
 for col_attr in mapper.column_attrs:
  column = col_attr.columns[0]
  if (column.default is not None):
   default_listener(col_attr, column.default)

def configure_listener ( mapper , class_ ) : for col_attr in mapper . column_attrs : column = col_attr . columns [ 0 ] if ( column . default is not None ) : default_listener ( col_attr , column . default )
establish attribute setters for every default-holding column on the given mapper .