def _get_file_conf(self, section, varname=None):
        """Gets the section from config file or raises an exception"""
        try:
            if not os.path.exists(self.config_filename):
                jwt_random_secret = ''.join(random.choice(string.ascii_letters) for _ in range(24))
                updown_random_secret = ''.join(random.choice(string.ascii_letters) for _ in range(24))
                server_conf = default_server_conf.format(jwt_secret=jwt_random_secret,
                                                         updown_secret=updown_random_secret)
                save(self.config_filename, server_conf)

            if not self._loaded:
                self._loaded = True
                self.read(self.config_filename)

            if varname:
                section = dict(self.items(section))
                return section[varname]
            else:
                return self.items(section)
        except NoSectionError as exc:
            raise ConanException(section % "No section '%s' found")
        except Exception as exc:
            logger.debug(exc)
            raise ConanException("Invalid configuration, "
                                 "missing %s: %s" % (section, varname))
dataset/ETHPy150Open conan-io/conan/conans/server/conf/__init__.py/ConanServerConfigParser._get_file_conf/swapped operands of `%`