code: public com.google.protobuf.ByteString
        getTypeHintBytes() {
      java.lang.Object ref = typeHint_;
      if (ref instanceof java.lang.String) {
        com.google.protobuf.ByteString b = 
            com.google.protobuf.ByteString.copyFromUtf8(
                (java.lang.String) ref);
        typeHint_ = b;
        return b;
      } else {
        return (com.google.protobuf.ByteString) ref;
      }
    }
docs: <pre>
  Hint on how plugins should process the data in this series.
  Supported values include "scalar", "histogram", "image", "audio"
  </pre>
  
  <code>optional string type_hint = 1;</code>