Represents the "1.3" entry of the opi version dictionary object.

It is an optional entry defined as part of the PDF 1.2 specification.

It contains a Version13OpiElement.

For definitive details see:.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 368, page 639.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 405, page 823.