configparser.ConfigParser.writer()

    ①
    write(fileobject, space_around_delimiters=True)

Write a representation of the configuration to the specified file object,which must be opened in text mode(accepting strings),This representation can ba parsed by a future read() call.if space_around_delimiters is true,delimiters between keys an values are surrounded by spaces.

config = configparser.Configparser()
must be opened in text mode (accept strings):只能使用text模式打开的文件才能被写入，with open('users.pkl', 'w') as f:
config.writer(f)

②
read(filenames, encoding=None)
            If filenames is a string or path-like object, it is treated as a single filename. If a file named in filenames cannot be opened, that file will be ignored. This is designed so that you can specify a list of potential configuration file locations (for example, the current directory, the user’s home directory, and some system-wide directory), and all existing configuration files in the list will be read.

If none of the named files exist, the ConfigParser instance will contain an empty dataset. An application which requires initial values to be loaded from a file should load the required file or files using read_file() before calling read() for any optional files:

    import configparser, os

config = configparser.ConfigParser()
config.read_file(open('defaults.cfg'))