import gc
import threading
import os
import sys

stdout_fd = sys.stdout.fileno()

def log(msg):
    msg = msg + "\n"
    msg = msg.encode("utf8")
    os.write(stdout_fd, msg)

def recursive_function():
    log("threading.enumerate")
    threading.enumerate()

class EvilGC:
    def __del__(self):
        log("EvilGC.__del__")
        recursive_function()

def create_ref_leaks():
    a = EvilGC()
    b = EvilGC()
    a.b = b
    b.a = a

def main():
    for i in range(10):
        log(f"-- loop {i} --")
        gc.set_threshold(1 + i)
        create_ref_leaks()
        recursive_function()

    gc.collect()

if __name__ == "__main__":
    main()