How to install letsencrypt on debian 8?

Do as told on of. the website

I had to add wheezy-backports as it is written here

But letsencrypt fails due to "unmet dependencies":
$ sudo apt-get install -t wheezy-backports letsencrypt
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 letsencrypt : Depends: python-letsencrypt (= 0.5.0-1~bpo8+1) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.


Trying to install dependencies:
# apt-get install -t wheezy-backports python-letsencrypt
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 python-letsencrypt : Depends: python-acme (>= 0.5.0) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

# apt-get install -t wheezy-backports python-acme
Reading package lists... Done
Building dependency tree
Reading state information... Done
python-acme is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 31 not upgraded.


list apt dependencies shows:
# apt list python-letsencrypt
Listing... Done
python-letsencrypt/jessie-backports 0.5.0-1~bpo8+1 all

# apt list python-acme
Listing... Done
python-acme/jessie-backports,now 0.6.0-1~bpo8+1 all [installed]


How it correctly to install?
July 9th 19 at 10:59
1 answer
July 9th 19 at 11:01
https://debian.pro/1925
https://debian.pro/2152

Place the packages in a specific version, it will be clearer what's going on.
apt-get install package=version-t repo

But in General, most likely, some meat from the repositories in your sources.list. Some testing is connected, for example.

Find more questions by tags Debian