def identifier(self, version: str) -> str:
        """
        Get identifier in the form my-dataset@v3.0.1
        """
        if not self.has_version(version):
            raise DatasetVersionNotFoundError(
                f"Dataset {self.name} doesn't have a version {version}"
            )
        return f"{self.name}@v{version}"

        Get identifier in the form my-dataset@v3.0.1
        
src/datachain/dataset.py