file_mounts:
  /outputs:
    name: romil-sky-outputs1 # This is a new unique bucket
    store: s3
    mode: MOUNT

run: |
  echo "Hello, world!" > /outputs/hello.txt

$ sky jobs logs --controller 1
...
(sky-4d6a-romilb, pid=30569) sky.exceptions.StorageSpecError: Attempted to mount a non-sky managed bucket 'romil-sky-outputs1' without specifying the storage source. Bucket 'romil-sky-outputs1' already exists.
(sky-4d6a-romilb, pid=30569)     • To create a new bucket, specify a unique name.
(sky-4d6a-romilb, pid=30569)     • To mount an externally created bucket (e.g., created through cloud console or cloud cli), specify the bucket URL in the source field instead of its name. I.e., replace `name: romil-sky-outputs1` with `source: s3://romil-sky-outputs1`.
ERROR: Job 1 failed with return code list: [1]