test.py

import gc

def task10():
    class Thanos:
        def __init__(self):
            self.ref = " "
        def __del__(self):
            pass
    
    class A:
        def __init__(self):
            pass
    
    
    gc.collect()
    t = Thanos()
    t2 = Thanos()
    t.ref = t
    t2.ref = t2
    a = []
    b = []
    p = A()
    a.append(b)
    b.append(a)
    # gc.collect()
    objects = gc.get_objects(0)
    
    del t
    del t2
    del p
    del b
    del a

    gc.collect()
    survivors = gc.get_objects()
    counter = 0
    
    for elem in objects:            
        for cmp_elem in survivors:
            if cmp_elem is elem:
                print(cmp_elem)
                counter += 1
    
    return counter

print("Задача 10:", task10())