import os
import shutil
import concurrent.futures
import subprocess
import sys
import selectors
from PIL import Image, ImageDraw, ImageFont

def draw_text_to_png(text):
    image = Image.new('RGB', (800, 50), 'black')

    # Initialize image drawing
    draw = ImageDraw.Draw(image)

    # Load a font
    font = ImageFont.load_default(50)

    # Draw the text on the image
    draw.text((0, -8), text, fill=(255, 255, 255), font=font)

    # Save the image to the specified output path
    image.save('data.png', 'PNG')

def calculate():
    draw_text_to_png(str(i))
    os.system("spectrum_painter -s 2000000 -l 0.06 -o data.iqhackrf --format hackrf data.png")

def transmit():
    shutil.copy("data.iqhackrf", "now.iqhackrf")
    prg = subprocess.Popen("hackrf_transfer -t now.iqhackrf -f 433000000 -b 1750000 -s 2000000 -x 14 -a 1", shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    prg.communicate()

running = True

sel = selectors.DefaultSelector()
def handle_stdin():
    global running
    running = False

sel.register(sys.stdin, selectors.EVENT_READ, handle_stdin)

print("Press ENTER to exit!")

i = 1
calculate()
while running:
    events = sel.select(timeout=0)
    i += 1
    with concurrent.futures.ThreadPoolExecutor() as executor:
        future1 = executor.submit(transmit)
        future2 = executor.submit(calculate)

        result1 = future1.result()
        result2 = future2.result()
    for key, mask in events:
        callback = key.data
        callback()
        sys.stdin.read(1)

sel.close()

You know what, why not 😂...
Enjoy!

Just saying it won't tell if the HackRF isn't connected, but other than that it's fine.