code: def summarise_pdfs(pdfs):
      
  
      # Ignore None.
      print('Summarising {0} articles ({1} had errors)'.format(
          len(pdfs), pdfs.count(None)))
      pdfs = [_ for _ in pdfs if _ is not None]
  
      summary = PdfFileWriter()
      for pdf in pdfs:
          summary.addPage(PdfFileReader(StringIO(pdf)).getPage(0))
      return summary
docs: Collate the first page from each of the PDFs provided into a single PDF.
  
      :param pdfs:
          The contents of several PDF files.
  
      :type pdfs:
          list of str
  
      :returns:
          The contents of single PDF, which can be written directly to disk.