root@di-01:~# do-release-upgrade
Checking for a new Ubuntu release
Traceback (most recent call last):
  File "/usr/bin/do-release-upgrade", line 145, in <module>
    fetcher.run_options += ["--mode=%s" % options.mode,
AttributeError: type object 'DistUpgradeFetcherCore' has no attribute 'run_options'
root@di-01:~# do-release-upgrade -d
Checking for a new Ubuntu release
Traceback (most recent call last):
  File "/usr/bin/do-release-upgrade", line 145, in <module>
    fetcher.run_options += ["--mode=%s" % options.mode,
AttributeError: type object 'DistUpgradeFetcherCore' has no attribute 'run_options'
root@di-01:~#