The Filename property holds the name of the file on disk where the Blob
stores its data. If not specified, FileBlob will create
a temporary file (in a temporary windows folder) which will be
deleted when FileBlob is destroyed.
You can specify your own filename if you want FileBlob
to read data from your file, or to store data to your
When you set this filename, the AutoDelete
property is changed internally to False (meaning
your file will not be deleted when the Blob is destroyed).