update docs for Ubuntu install

Author: clovis

docs/specific_installations/ubuntu_installation.md

@@ -18,7 +18,7 @@ title: Installing PhiloLogic4 on Ubuntu
 
     `sudo apt-get install libxml2-dev libxslt-dev zlib1g-dev apache2 libgdbm-dev liblz4-tool brotli ripgrep`
 
-- Install pip3 (not the version from Ubuntu repos since it breaks pyproject.toml builds)
+- Install pip3 (not the version from Ubuntu repos since it breaks pyproject.toml builds). First delete the python3-setuptools Ubuntu package if present: `sudo apt purge python3-setuptools`, then run:
     `wget https://bootstrap.pypa.io/get-pip.py && python3 get-pip.py`
 
 -   Run install script inside the PhiloLogic4 directory