code: def file_claims_pdfa(filename):
      
  
      with pikepdf.open(filename) as pdf:
          pdfmeta = pdf.open_metadata()
          if not pdfmeta.pdfa_status:
              return {
                  'pass': False,
                  'output': 'pdf',
                  'conformance': 'No PDF/A metadata in XMP',
              }
          valid_part_conforms = {'1A', '1B', '2A', '2B', '2U', '3A', '3B', '3U'}
          conformance = f'PDF/A-{pdfmeta.pdfa_status}'
          pdfa_dict = {}
          if pdfmeta.pdfa_status in valid_part_conforms:
              pdfa_dict['pass'] = True
              pdfa_dict['output'] = 'pdfa'
          pdfa_dict['conformance'] = conformance
      return pdfa_dict
docs: Determines if the file claims to be PDF/A compliant
  
      This only checks if the XMP metadata contains a PDF/A marker. It does not
      do full PDF/A validation.