code: public com.google.protobuf.ByteString
        getDeprecationDescriptionBytes() {
      java.lang.Object ref = deprecationDescription_;
      if (ref instanceof java.lang.String) {
        com.google.protobuf.ByteString b = 
            com.google.protobuf.ByteString.copyFromUtf8(
                (java.lang.String) ref);
        deprecationDescription_ = b;
        return b;
      } else {
        return (com.google.protobuf.ByteString) ref;
      }
    }
docs: <pre>
  Deprecation description of the selected element(s). It can be provided if an
  element is marked as `deprecated`.
  </pre>
  
  <code>string deprecation_description = 3;</code>