Install Python packages into virtualenv

.config/i3/layers/config.post-main-01-visuals

@@ -2,7 +2,7 @@
 exec_always --no-startup-id pidof -s picom || picom
 
 # Run flashfocus
-exec_always --no-startup-id flashfocus --config ~/.config/flashfocus/flashfocus.yml
+exec_always --no-startup-id $flashfocus_bin --config ~/.config/flashfocus/flashfocus.yml
 bindsym Alt+section exec --no-startup-id flash_window
 
 # Set wallpaper

.config/i3/layers/config.pre-main-00-vars

@@ -13,3 +13,5 @@ set $calc_cmd kitty --title calculator bc -l
 
 set $browser firefox
 set $terminal kitty
+
+set $flashfocus_bin /opt/dotfiles/pyenv/bin/flashfocus

setup_system.sh

@@ -11,6 +11,8 @@ script_dir="$(
     cd -- "$(dirname "$0")" >/dev/null 2>&1 || exit 1
     pwd -P
 )"
+opt_dir=/opt/dotfiles
+python_venv=$opt_dir/pyenv
 
 #
 # Argument parsing and help
@@ -79,8 +81,18 @@ function construct_target_list() {
 }
 
 function setup_pip_packages() {
+    echo "Installing Python packages into virtualenv $python_venv"
+
+    ! [ -d "$opt_dir" ] && sudo mkdir "$opt_dir"
+    sudo python -m venv "$python_venv"
+
+    # shellcheck disable=SC1091
+    source "$python_venv/bin/activate"
+
     # shellcheck disable=SC2046
     sudo pip3 install $(get_packages $(construct_target_list pip)) --no-input || return 1
+
+    deactivate
 }
 
 function install_sddm_aerial_theme() {