def row_completed(self, index):
self._completed_rows.append(index)<EOL>for row_completed in self._on_row_completed:<EOL><INDENT>row_completed(index)<EOL><DEDENT>
Mark the row at index as completed.

        .. seealso:: :meth:`completed_row_indices`

        This method notifies the obsevrers from :meth:`on_row_completed`.