def external_editor(self, filename, goto=-1):
        """Edit in an external editor
        Recommended: SciTE (e.g. to go to line where an error did occur)"""
        editor_path = CONF.get('internal_console', 'external_editor/path')
        goto_option = CONF.get('internal_console', 'external_editor/gotoline')
        try:
            args = [filename]
            if goto > 0 and goto_option:
                args.append('%s%d'.format(goto_option, goto))
            programs.run_program(editor_path, args)
        except OSError:
            self.write_error("External editor was not found:"
                             " %s\n" % editor_path)