Can't install pgAdmin 4 on 20.04 LTS

I was able to install pgadmin4 on ubuntu 20.04 (focal fossa) using the following article as a base: https://linuxhint.com/install-pgadmin4-ubuntu/

A few changes to the instructions are required:

1. In part 2:

   sudo apt-get install build-essential libssl-dev libffi-dev libgmp3-dev
   sudo apt-get install python3-virtualenv libpq-dev python3-dev
   

2. In part 5:
   The latest version for the moment is:

   https://ftp.postgresql.org/pub/pgadmin/pgadmin4/v4.20/pip/pgadmin4-4.20-py2.py3-none-any.whl
   

   (I used release, not a daily snapshot)

3. In part 6: Use

   pip install pgadmin4-4.20-py2.py3-none-any.whl 
   

4. In part 7:
   Use 'python3.8' instead of 'python2.7'

That's all.
Worked for me.

Update: Please note that it's possible install pgadmin4 (4.21) directly from the repositories now.

The problem of the upstream debian repository was the python 3.8 support. They said that was fixed in this commit, but they are apparently missing this: https://github.com/postgres/pgadmin4/commit/b7dad25d3eb29fae05fef4f161dea644f080276f

Also the upstream has no support for Ubuntu 20.04 yet. See the status at this date (2020-05-13): https://www.postgresql.org/ftp/pgadmin/pgadmin4/snapshots/

If someone were to distribute pgadmin4 directly in Ubuntu it would be really helpfully, but it is not available yet.