def handle_error(result):
if result:<EOL><INDENT>return<EOL><DEDENT>_, error_string = get_error()<EOL>if not isinstance(error_string, str_cls):<EOL><INDENT>error_string = _try_decode(error_string)<EOL><DEDENT>raise OSError(error_string)<EOL>
Extracts the last Windows error message into a python unicode string

:param result:
    A function result, 0 or None indicates failure

:return:
    A unicode string error message