Step 1: Download Backblaze B2 Command Line Tool
Remember DURING install to choose to set PIP environmental Path
https://www.backblaze.com/b2/docs/quick_command_line.html or https://www.backblaze.com/b2/docs/quick_command_line.html#download

If you run into issues with PIP:
http://strongitguy.com/issues-setting-up-b2-command-line-and-windows-python-install/

Backblaze documentation has an [-h] in it, remove this.

b2 authorize-account ID Appkey
(replace ID and APPKEY with the one you received from Dropbox)

Commands to run once CLI is setup:

b2 list-buckets

b2 list-unfinished-large-files bucketname

b2 cancel-all-unfinished-large-files bucketname
Removes all unfinished files (per Backblaze Support)