Graphlib errors on install

[maxleonca]

Installer is missing a dependency and when installed by hand, gives an error.
Install is missing graphlib and when install by hand and executes errbot --init an error about CycleError not being able to be imported.

To Reproduce
On an Ubuntu 20.04 execute the following steps:

• virtualenv --python which python3 ~/.errbot-ve ─╯
• ~/.errbot-ve/bin/pip install errbot
• source ~/.errbot-ve/bin/activate
• errbot --init (1st error about graphlib not being available is displayed)
• pip install graphlib
• errbot --init (2nd error about not being able to import CycleError from graphlib is displayed)

Expected behavior
By following the documentation you should be able to install errbot and initialize it without errors.

Screenshots

Environment (please complete the following information):

• Errbot version: errbot==6.2.0
• OS version: Ubuntu 20.04
• Python version: Python 3.8.10
• Using a virtual environment: yes
• Using Docker: no

Additional context
Add any other context about the problem here.

[nzlosh]

Python3.8 requires a specific wheel to be created that includes the missing module which isn't available at the moment. Your options are:

1. Wait for the wheel to be created and pushed to PyPi
2. Use a new OS that has a newer version of Python3. 3.9/3.10/3.11 are tested as working for errbot.
3. Install errbot from github which will install the missing module for py3.8.
4. Install the missing module in the virtualenv by hand pip install graphlib-backport==1.0.3

[maxleonca]

Thank you so very much!