def test_multiple_metavar_help(self, parser: parseopt.Parser) -> None:
        """
        Help text for options with a metavar tuple should display help
        in the form "--preferences=value1 value2 value3" (#2004).
        """
        group = parser.getgroup("general")
        group.addoption(
            "--preferences", metavar=("value1", "value2", "value3"), nargs=3
        )
        group._addoption("-h", "--help", action="store_true", dest="help")
        parser.parse(["-h"])
        help = parser.optparser.format_help()
        assert "--preferences=value1 value2 value3" in help

        Help text for options with a metavar tuple should display help
        in the form "--preferences=value1 value2 value3" (#2004).
        
testing/test_parseopt.py