LDAP Sync installation problem in Ubuntu

I tried to install LDAP sync on a fresh Ubuntu Bionic based Ralph installation with this guide:

https://ralph-ng.readthedocs.io/en/stable/installation/configuration/

The command “pip install -r requirements/prod_ldap.txt” gives the following error:

“Could not open requirements file: [Errno 2] No such file or directory: ‘requirements/prod_ldap.txt’”

The guide also tells that more information can be found here: http://packages.python.org/django-auth-ldap - but this address doesn’t work.

Thus I googled for django-auth-ldap and the official page for django-auth-ldap (link removed because of limitations).

Now I have django-auth-ldap installed, but I have no clue where to add the local settings nor django-auth-ldap settings.

Should the django-auth-ldap settingsg naybe go here? /opt/ralph/ralph-core/lib/python3.6/site-packages/django_extensions/settings.py

So my main question is: Where do I add these configuration parameters? I know what to add, but not where to add them.

One more side note: many guides tell I should run “ralph”, but I only have ralphctl - is this the same command?

Has anyone made an installation guide for newbies?

Can anyone give me a hand with this?