Initial setup, run once.

def _setup(self):
        """Initial setup, run once."""
        default_settings.reload()
        environment_variable = self._kwargs.get(
            "ENVVAR_FOR_DYNACONF", default_settings.ENVVAR_FOR_DYNACONF
        )
        settings_module = os.environ.get(environment_variable)
        self._wrapped = Settings(
            settings_module=settings_module, **self._kwargs
        )
        self.logger.debug("Lazy Settings _setup ...")