$ curl cheat.sh/
 cheat.sheets:apt-key 
# apt-key
# Command-line APT key management utility

# List APT keys marked as trusted.
apt-key list

 tldr:apt-key 
# apt-key
# Key management utility for the APT Package Manager on Debian and Ubuntu.
# Note: `apt-key` is now deprecated (except for the use of `apt-key del` in maintainer scripts).
# More information: <https://manpages.debian.org/latest/apt/apt-key.8.html>.

# List trusted keys:
apt-key list

# Add a key to the trusted keystore:
apt-key add public_key_file.asc

# Delete a key from the trusted keystore:
apt-key del key_id

# Add a remote key to the trusted keystore:
wget -qO - https://host.tld/filename.key | apt-key add -

# Add a key from keyserver with only key id:
apt-key adv --keyserver pgp.mit.edu --recv KEYID

$
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