This file is used to convert between XenServer .xva files and opensource Xen .img files. The old script (graciously by Jolokia Networks) and provided by https://github.com/hswayne77 seems out of date and does not run. Instead, when used from the prompt a an error will be displayed:
"UnboundLocalError: local variable 'source' referenced before assignment"
Script was slightly modified by me to fix this.