I ran 
apt-get update
apt-get dist-upgrade

and also

apt-get update
apt-get install confconsole python-bottle authbind
apt-get install -t jessie-backports dehydrated

get

dehydrated is already the newest version.

But still get same error when running /usr/lib/confconsole/plugins.d/Lets_Encrypt/dehydrated-wrapper

Thanks

Paul