INSTALL
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Install gnupg and python3-gpg

Example:
1. generate a gnupg certificate without password.
2. run "gpg_websocket.py" from the user account with gpg private key.
3. install webserver with php support to test demo.php.
4. update "$pubkey" and YOUR_KEY_ID with your public-key and key-id.
5. now you can test demo.php.