Hi. Thanks for the PR, nice idea 👍
Looking at the code base, I see that we already have the properties

• User.name
• User.full_name
• Chat.full_name

and your PR basically copiesUser.name andChat.full_name toSharedUser.
To avoid too much duplication, I would like you instead introduce a new moduletelegram._utils.usernames whith two functionget_name andget_full_name. They would both accept a object of type

classUserLike(typing.Protocol):first_name:typing.Optional[str]last_name:typing.Optional[str]username:typing.Optional[str]

Would that be doable for you?

Note that you can copy the tests fromtest_chat/test_user. I'd like to avoid introducingunittest into our test suite b/c we use nowhere else.

Closing in favor of#4713