def METHOD_NAME(self, config: Mapping[str, Any]):
    logger = logging.getLogger("airbyte")
    source_spec = self.spec(logger)
    default_project_timezone = source_spec.connectionSpecification["properties"]["project_timezone"]["default"]
    config["project_timezone"] = pendulum.timezone(config.get("project_timezone", default_project_timezone))
    today = pendulum.today(tz=config["project_timezone"]).date()
    start_date = config.get("start_date")
    if start_date:
        config["start_date"] = pendulum.parse(start_date).date()
    else:
        config["start_date"] = today.subtract(days=365)
    end_date = config.get("end_date")
    if end_date:
        config["end_date"] = pendulum.parse(end_date).date()
    else:
        config["end_date"] = today
    for k in ["attribution_window", "select_properties_by_default", "region", "date_window_size"]:
        if k not in config:
            config[k] = source_spec.connectionSpecification["properties"][k]["default"]
    auth = self.get_authenticator(config)
    if isinstance(auth, TokenAuthenticatorBase64) and "project_id" in config:
        config.pop("project_id")
    elif isinstance(auth, BasicHttpAuthenticator) and "project_id" not in config:
        raise ValueError("missing required parameter 'project_id'")
    return config