CLI install-requirements ~ failed to install

Hej-hej Robin,

it did not succeed to install the rdflib requirements:

[sudo] Passwort für root: 
Collecting rdflib
  Downloading rdflib-5.0.0-py3-none-any.whl (231 kB)
     |████████████████████████████████| 231 kB 1.5 MB/s 
Requirement already satisfied: requests in /usr/lib/python3.6/site-packages (2.26.0)
Requirement already satisfied: pyparsing in /usr/lib/python3.6/site-packages (from rdflib) (2.4.7)
Requirement already satisfied: six in /usr/lib/python3.6/site-packages (from rdflib) (1.16.0)
Collecting isodate
  Downloading isodate-0.6.0-py2.py3-none-any.whl (45 kB)
     |████████████████████████████████| 45 kB 509 kB/s 
Requirement already satisfied: certifi>=2017.4.17 in /usr/lib/python3.6/site-packages (from requests) (2021.5.30)
Requirement already satisfied: urllib3<1.27,>=1.21.1 in /usr/lib/python3.6/site-packages (from requests) (1.26.7)
Requirement already satisfied: charset_normalizer~=2.0.0 in /usr/lib/python3.6/site-packages (from requests) (2.0.7)
Requirement already satisfied: idna<4,>=2.5 in /usr/lib/python3.6/site-packages (from requests) (3.3)
Installing collected packages: isodate, rdflib
Successfully installed isodate-0.6.0 rdflib-5.0.0
Klone nach '/home/andreas/src/ontology-visualization' ...
remote: Enumerating objects: 106, done.
remote: Counting objects: 100% (5/5), done.
remote: Compressing objects: 100% (4/4), done.
remote: Total 106 (delta 1), reused 1 (delta 0), pack-reused 101
Empfange Objekte: 100% (106/106), 31.15 KiB | 3.46 MiB/s, Fertig.
Löse Unterschiede auf: 100% (54/54), Fertig.
ERROR: Could not find a version that satisfies the requirement rdflib<7.0.0,>=6.0.0 (from -r /home/andreas/src/ontology-visualization/requirements.txt (line 1)) (from versions: 2.4.1, 2.4.2, 3.0.0, 3.1.0, 3.2.0, 3.2.1, 3.2.2, 3.2.3, 3.4.0, 4.0, 4.0.1, 4.1.0, 4.1.1, 4.1.2, 4.2.0, 4.2.1, 4.2.2, 5.0.0rc1, 5.0.0)
ERROR: No matching distribution found for rdflib<7.0.0,>=6.0.0 (from -r /home/andreas/src/ontology-visualization/requirements.txt (line 1))

The requirements are:

cat /home/andreas/src/ontology-visualization/requirements.txt
# rdflib >= 6.0.0, < 7.0.0
# graphviz == 0.17

So what to do?

Or even how to uninstall and clean it? (see related issue #1)

Regards, Andreas