def read_config_files(self, files):
        """Read a list of config files.

        :param iterable files: An iterable (e.g. list) of files to read.
        """
        errors = {}
        for _file in files:
            config, valid = self.read_config_file(_file)
            self.update(config)
            if valid is not True:
                errors[_file] = valid
        return errors or True
Read a list of config files.

        :param iterable files: An iterable (e.g. list) of files to read.