This particular part of the Traceback seems worth fixing:
File "/tmp/ubuntu-release-upgrader-4aooz0fb/DistUpgrade/DistUpgradeController.py", line 1166, in doDistUpgrade
self._view.getTerminal().call(cmd)
File "/tmp/ubuntu-release-upgrader-4aooz0fb/DistUpgrade/DistUpgradeViewGtk3.py", line 377, in call
(success, pid) = self.term.spawn_sync(Vte.PtyFlags.DEFAULT,
AttributeError: 'Terminal' object has no attribute 'spawn_sync'
This particular part of the Traceback seems worth fixing:
File "/tmp/ubuntu- release- upgrader- 4aooz0fb/ DistUpgrade/ DistUpgradeCont roller. py", line 1166, in doDistUpgrade _view.getTermin al().call( cmd) release- upgrader- 4aooz0fb/ DistUpgrade/ DistUpgradeView Gtk3.py" , line 377, in call spawn_sync( Vte.PtyFlags. DEFAULT,
self.
File "/tmp/ubuntu-
(success, pid) = self.term.
AttributeError: 'Terminal' object has no attribute 'spawn_sync'