How to terminate a Python3 thread correctly while it's reading a stream

I'm using a thread to read Strings from a stream (/dev/tty1) while processing other things in the main loop. I would like the Thread to terminate together with the main program when pressing CTRL-C.

   from threading import Thread

   class myReader(Thread):
      def run(self):
         with open('/dev/tty1', encoding='ascii') as myStream:
            for myString in myStream:
               print(myString)
      def quit(self):
         pass # stop reading, close stream, terminate the thread

   myReader = Reader()
   myReader.start()
   while(True):
      try:
         pass # do lots of stuff
      KeyboardInterrupt:
         myReader.quit()
         raise

The usual solution - a boolean variable inside the run() loop - doesn't work here. What's the recommended way to deal with this?

I can just set the Daemon flag, but then I won't be able to use a quit() method which might prove valuable later (to do some clean-up). Any ideas?