def METHOD_NAME(self) -> Sequence[str]:
    try:
        if self._last_rcc_settings is None:
            configuration_settings = self._rcc.configuration_settings()
            if configuration_settings.success and configuration_settings.result:
                settings = json.loads(configuration_settings.result)
                self._last_rcc_settings = settings
            else:
                self._last_rcc_settings = None
    except Exception:
        self._last_rcc_settings = None
        log.exception("Error getting pypi base urls.")
    settings = self._last_rcc_settings
    if isinstance(settings, dict):
        endpoints = settings.get("endpoints")
        if isinstance(endpoints, dict):
            pypi = endpoints.get("pypi-trusted")
            if isinstance(pypi, str):
                pypi = pypi.strip()
                if pypi and not pypi.startswith("#"):
                    if pypi.endswith("/"):
                        pypi = pypi[:-1]
                    # RCC passes the additional index but does
                    # not stop pass --no-index to stop indexing pypi.org
                    # See: https://pip.pypa.io/en/stable/cli/pip_install/
                    return (pypi, "https://pypi.org")
    return ("https://pypi.org",)