File Load Error

[gdbassett]

previously I used https://github.com/uktrade/jupyters3 for an s3 filesystem. We recently switched to s3contents since it's still supported. However for notebooks previously saved with jupyters3, often when we try and open them we get "file load error for Not Found". It may be due to the backup directories and notebooks having the same name. (Jupyters3 hides the backup directories.) If we go into the s3 bucket and create a copy of the notebook, it works fine.