if 'port' not in config: config['port'] = 80 port = config['port'] Setting default values to dictionaries can be done more elegant: config = config.setdefault('port', 80) setdefault sets the new value unless some value is already set. It also returns the new stored value whether it was changed or not: In : config = {} In : config.setdefault('port', 80) Out: 80 In : config.setdefault('port', 443) Out: 80