Issue python3.6 while inheriting telnet library

[sourabhjaiswal92]

I am trying to create below hierarchy in my python code. But I am facing some issue when I am inheriting telnet library. This issue is coming in python 3.6.

import telnetlib
class A(telnetlib.Telnet):
    def __init__(self):
        print("init A")
        super(A, self).__init__()

class B(object):
    def __init__(self):
        print("init B")
        super(B, self).__init__()

class C(B):
    def __init__(self):
        print("init C")
        super(C, self).__init__()

class D(object):
    def __init__(self):
        print("init D")
        super(D, self).__init__()

class E(C,D):
    def __init__(self):
        print("init E")
        super(E, self).__init__()

class F(A,E):
    def __init__(self):
        print("init F")
        super(F, self).__init__()

if __name__ == '__main__':
    F()

Output in python3.6:-

Output:
init F
init A

Output in python2.7:-

Output:
init F
init A
init E
init C
init B
init D
Exception AttributeError: "'F' object has no attribute 'sock'" in <bound method F.__del__ of <__main__.F object at 0x7f6a9f36a6d0>> ignored

Output in python3.6 without telnet library:-

Output:
init F
init A
init E
init C
init B
init D

if I run the same code and derive class 'A' from object instead of telnetlib.Telnet the constructor calling works fine.

Can somebody please guide me here, What I am doing wrong. I am really stuck here.

The same code works perfectly fine with python 2.7.

Thanks in advance!

Regards, Sourabh Jaiswal