    def modified(self, path, version_id=None, refresh=False):
        """Return the last modified timestamp of file at `path` as a datetime"""
        info = self.info(path=path, version_id=version_id, refresh=refresh)
        if "LastModified" not in info:
            # This path is a bucket or folder, which do not currently have a modified date
            raise IsADirectoryError
        return info["LastModified"]
Return the last modified timestamp of file at `path` as a datetime
s3fs/core.py