This bash script sets the mac wallpaper from a label

wp.sh

#!/usr/bin/env bash
# ────────────────────────────────────────────────────────────────────────────
#  make-wallpaper.sh  •  macOS  •  ask for a label → black 4-K JPEG wallpaper
# ────────────────────────────────────────────────────────────────────────────
set -euo pipefail

read -p "Enter the label to show on the wallpaper: " LABEL
[[ -z $LABEL ]] && { echo "No text entered – aborting."; exit 1; }

export LABEL                                  # pass into Python
export JPEG="/tmp/wallpaper_${LABEL// /_}.jpg"

python3 - <<'PY'
import os, sys, subprocess, importlib

def have_pillow() -> bool:
    try:
        import PIL                 # noqa: F401
        return True
    except ModuleNotFoundError:
        return False

if not have_pillow():
    print("• Pillow not found – installing to your user site …")
    # 1) make sure pip exists
    try:
        subprocess.check_call([sys.executable, "-m", "pip", "--version"],
                              stdout=subprocess.DEVNULL,
                              stderr=subprocess.DEVNULL)
    except subprocess.CalledProcessError:
        print("  (bootstrapping pip…)")                        # macOS CLT Python
        subprocess.check_call([sys.executable, "-m", "ensurepip", "--upgrade"])
    # 2) install pillow
    try:
        subprocess.check_call([sys.executable, "-m", "pip",
                               "install", "--quiet", "--user", "pillow"])
    except subprocess.CalledProcessError:
        print("❌  PIP failed. Run this then re-launch the script:\n"
              "   python3 -m pip install --user pillow")
        sys.exit(1)
    import importlib
    importlib.invalidate_caches()

if not have_pillow():
    print("❌  Pillow still missing after install. Run:\n"
          "   python3 -m pip install --user pillow")
    sys.exit(1)

# ── build the image ─────────────────────────────────────────────────────────
from PIL import Image, ImageDraw, ImageFont   # type: ignore

label  = os.environ["LABEL"]
out    = os.environ["JPEG"]
W, H   = 3840, 2160
img    = Image.new("RGB", (W, H), "black")
draw   = ImageDraw.Draw(img)

fonts = ["/System/Library/Fonts/SFNS.ttf",
         "/System/Library/Fonts/SFNSText.ttf",
         "/System/Library/Fonts/Helvetica.ttc"]
fontpath = next((p for p in fonts if os.path.exists(p)), None)
size     = int(H * 0.55)
font     = ImageFont.truetype(fontpath, size) if fontpath else ImageFont.load_default()
while draw.textlength(label, font=font) > W * 0.9:
    size -= 10
    font  = ImageFont.truetype(fontpath, size) if fontpath else ImageFont.load_default()

draw.text(((W - draw.textlength(label, font=font)) / 2,
           (H - font.size) / 2),
          label, font=font, fill="white")
img.save(out, "JPEG", quality=95)
print("• Created", out)
PY

# ── apply it to every Desktop/Space ─────────────────────────────────────────
osascript - "$JPEG" <<'OSA'
on run argv
  set p to POSIX file (item 1 of argv)
  tell application "System Events"
    repeat with d in desktops
      set picture of d to p
    end repeat
  end tell
end run
OSA

echo "✔ Wallpaper applied!"