telethon.tl.types.Message is unhashable after upgraded to 0.17+

After upgrade from 0.16.2.x to 0.17+, our App broken due to telethon.tl.types.Message become unhashable. Following is a simple test case to reproduce this issue:

from telethon.tl.types import Message

print('Message.__hash__:', Message.__hash__)
msg = Message(1, None, None, 'Testing 1')
testSet = set([msg])
testSet |= set([msg])
print('testSet: ', testSet)

Output from 0.16.2.3:

telethon-0.16.2.3>pip3 install telethon==0.16.2.3
telethon-0.16.2.3>test_case.py
Message.__hash__: <slot wrapper '__hash__' of 'object' objects>
testSet:  {<telethon.tl.types.Message object at 0x017B0BF0>}

Output from 0.17.4.5:

telethon-0.16.2.3>pip3 install telethon==0.17.4.5
telethon-0.17.4.5>test_case.py
Message.__hash__: None
Traceback (most recent call last):
  File "...\test_case.py", line 5, in <module>
    testSet = set([msg])
TypeError: unhashable type: 'Message'

[Lonami]

I was unaware TLObjects ever were hashable. You can obj.to_dict() instead and pick what you need. Or make a dict by {msg.id: msg}.

[Lonami]

Your solution then is {id(obj): obj} and .update() it, or setting TLObject.__hash__ = lambda self: id(self).