The VERSIONS.get_version returned a Version object instead of a string,
it will raise ValueError: Circular reference detected when json encode.
This issue was introduced by commit
834722cf8af7b3471e9c7234da0bac8669025ca2
Change-Id: Ib41b2f7e77ac49911e9d5a4e129047f941bf5d24
Closes-bug: #1672291