_____ _ ____ __ __ _____ | || | / || |__| |/ ___/ | __|| | | o || | | ( \_ | |_ | |___ | || | | |\__ | | _] | || _ || ` ' |/ \ | | | | || | | \ / \ | |__| |_____||__|__| \_/\_/ \___|
There is an RFC on it (RFC-3927), but you should read the AWS specific docs on it here.
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