def METHOD_NAME(self):
    for key, value in self.config.properties.items():
        if isinstance(value, list):
            if key == "tags":
                self.config.properties[key] = ",".join(value)
            else:
                self.config.properties[key] = "|".join(value)
        elif isinstance(value, datetime):
            self.config.properties[key] = str(value)