Users new to Linux/Unix who have installed WeeWX via the 'pip' method are frequently confused when they run a command as indicated in the WeeWX documentation and get a 'command not found' message.

pi@pi4p1:~ $ weectl extension list
weectl: command not found

The problem here is that pip installations of weewx require you to activate the python virtual environment before running weewx commands

Activate your python virtual environment first...

pi@pi4p1:~ $ source ~/weewx-venv/bin/activate
pi@pi4p1:~ weectl extension list
Extension Name    Version   Description
mqtt              0.23      Upload weather data to MQTT server.

• for $PATH details, see the wiki page Understanding paths
• for where things are located, see the User's Guide