Search users in groups (and in which groups is the user) by id, username or phone number (if it's in your contacts).
To use this tool you need Telegram API creds. After you registered a new app, edit api_creds.ini file accordingly.
You need to install the requirements first.
python3 telescan.py api_creds.ini
To know if a user is in a group, you have to be in that group too. You can't know which users are in a specific channel if you are not an administrator.
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