type_url: "type.googleapis.com/google.crypto.tink.HmacKey"
# value: [type.googleapis.com/google.crypto.tink.HmacKeyFormat] {
#   params {
#     hash: SHA512
#     tag_size: 64
#   }
#   key_size: 64
#   version: 0
# }
value: "\n\004\010\004\020@\020@"
output_prefix_type: TINK
