code: def pdfa_status(self):
          
          key_part = QName(XMP_NS_PDFA_ID, 'part')
          key_conformance = QName(XMP_NS_PDFA_ID, 'conformance')
          try:
              return self[key_part] + self[key_conformance]
          except KeyError:
              return ''
docs: Returns the PDF/A conformance level claimed by this PDF, or False
  
          A PDF may claim to PDF/A compliant without this being true. Use an
          independent verifier such as veraPDF to test if a PDF is truly
          conformant.
  
          Returns:
              str: The conformance level of the PDF/A, or an empty string if the
              PDF does not claim PDF/A conformance. Possible valid values
              are: 1A, 1B, 2A, 2B, 2U, 3A, 3B, 3U.