type_url: "type.googleapis.com/google.crypto.tink.HmacKey"
# value: [type.googleapis.com/google.crypto.tink.HmacKeyFormat] {
#   params {
#     hash: SHA256
#     tag_size: 16
#   }
#   key_size: 32
#   version: 0
# }
value: "\n\004\010\003\020\020\020 "
output_prefix_type: TINK
