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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def from_configfile(self, configfile):
 """ Initialize the authentication store from a "config"-style file. Auth "config" file is parsed with C{ConfigParser.RawConfigParser} and must contain an [auth] section which contains the usernames (keys) and passwords (values). Example auth file:: [auth] someuser = somepass anotheruser = anotherpass @param configfile: Path to config file or file-like object. @type configfile: C{any} @raise ValueError: If file could not be read or does not contain [auth] section. """

        cfg = ConfigParser()
        if hasattr(configfile, 'read'):
            cfg.read_file(configfile)
        else:
            filesread = cfg.read(configfile)
            if not filesread:
                raise ValueError('Could not parse auth file: %s' % configfile)

        if not cfg.has_section('auth'):
            raise ValueError('Config file contains no [auth] section.')

        self.store = dict(cfg.items('auth'))