As discussed in the dev chat a while ago, I think it's time to head for a v22 release. Not to indroudce new breaking changes, but to put v20 deprecations to rest :)

A probably incomplete list of things deprecated in v20.x:

• default value of media_write_timeout
• Argument quote of Message.reply_*
• Return type of PassportElementErrors.file_hashes
• type of PassportFile.file_date (update test_official/exceptions.py accordingly)
• constants.InlineQueryLimit.MIN_SWITCH_PM_TEXT_LENGTH
• *_timeout parameter of Application.run_polling and Updater.start_polling
• input type of Application.create_task
  Edit: Nothing to do here. It can still work until we drop Py3.11 and then we can remove some logic.
• ApplicationBuilder.proxy_url/get_updates_proxy_url and HTTPXRequest.proxy_url
• defaults.disable_web_page_preview & quote
• filters.CHAT & filters.StatusUpdate.USER_SHARED
• EncryptedPassportElement.credentials