Generate a resource for ``create`` or ``update``.

def _build_resource(self):
        """Generate a resource for ``create`` or ``update``."""
        resource = {"name": self.name}

        if self.dns_name is not None:
            resource["dnsName"] = self.dns_name

        if self.description is not None:
            resource["description"] = self.description

        if self.name_server_set is not None:
            resource["nameServerSet"] = self.name_server_set

        return resource