I wanted to install containernet (Mininet) on Ubuntu 20.4 I got this error although I already installed (cgroup-tools)
the command I typed
sudo ansible-playbook -i "localhost," -c local install.yml
the error message

fatal: [localhost]: FAILED! => {"changed": true, "cmd":

 "containernet/util/install.sh", "delta": "0:00:05.640086", "end": "2020-09-01 16:09:32.350865", "msg": "non-zero return code", "rc": 100, 

"start": "2020-09-01 16:09:26.710779", "stderr": "E: Package 'cgroup-bin' 

has no installation candidate", "stderr_lines": ["E: Package 'cgroup-bin' 

has no installation candidate"], "stdout": "Detected Linux distribution: 

Ubuntu 20.04 focal amd64

python3 is version 3

Installing all packages 

except for -eix (doxypy, ivs, nox-classic)...

Install Mininet-compatible 

kernel if necessary

Hit:1 http://au.archive.ubuntu.com/ubuntu focal 

InRelease

Hit:2 https://download.docker.com/linux/ubuntu focal 

InRelease

Hit:3 http://au.archive.ubuntu.com/ubuntu focal-updates 

InRelease

Hit:4 http://au.archive.ubuntu.com/ubuntu focal-backports 

InRelease

Hit:5 http://security.ubuntu.com/ubuntu focal-security 

InRelease

Reading package lists...

Reading package lists...

Building 

dependency tree...

Reading state information...

linux-image-5.4.0-42-

generic is already the newest version (5.4.0-42.46).

The following package 

was automatically installed and is no longer required:

  libfprint-

2-tod1

Use 'sudo apt autoremove' to remove it.

0 to upgrade, 0 to newly 

install, 0 to remove and 0 not to upgrade.

Installing Mininet 

dependencies

Reading package lists...

Building dependency tree...

Reading 

state information...

Package cgroup-bin is not available, but is referred 

to by another package.

This may mean that the package is missing, has been 

obsoleted, or

is only available from another source

However the following 

packages replace it:

  cgroup-tools", "stdout_lines": ["Detected Linux 

distribution: Ubuntu 20.04 focal amd64", "python3 is version 3", "Installing 

all packages except for -eix (doxypy, ivs, nox-classic)...", "Install 

Mininet-compatible kernel if necessary", "Hit:1 http://au.archive.ubuntu.com

/ubuntu focal InRelease", "Hit:2 https://download.docker.com/linux/ubuntu 

focal InRelease", "Hit:3 http://au.archive.ubuntu.com/ubuntu focal-updates 

InRelease", "Hit:4 http://au.archive.ubuntu.com/ubuntu focal-backports 

InRelease", "Hit:5 http://security.ubuntu.com/ubuntu focal-security 

InRelease", "Reading package lists...", "Reading package lists...", 

"Building dependency tree...", "Reading state information...", "linux-image-

5.4.0-42-generic is already the newest version (5.4.0-42.46).", "The 

following package was automatically installed and is no longer required:", "  

libfprint-2-tod1", "Use 'sudo apt autoremove' to remove it.", "0 to upgrade, 

0 to newly install, 0 to remove and 0 not to upgrade.", "Installing Mininet 

dependencies", "Reading package lists...", "Building dependency tree...", 

"Reading state information...", "Package cgroup-bin is not available, but is 

referred to by another package.", "This may mean that the package is 

missing, has been obsoleted, or", "is only available from another source", 

"However the following packages replace it:", "  cgroup-tools"]}

How can I fix it?