I have written a Python function that uses multithreading.
def image(link_ID):
    tid1 = Thread(target=displayImage, args=(link_ID,))
    tid2 = Thread(target=publishIAmFree)
    tid1.start()
    tid2.start()
Function displayImage() simply puts up the image and the function publishIAmFree() publishes data to the broker and returns a FLAG value. 
How will I get the return value from the publishIAmFree() function, while in the thread?
 
    