title: Value Error: row index was 65536 , not allowed by xls. format , how to fix this error
body: <p>i have a file contain more than 950,000 rows , 
  When I convert file from Text to xls, it gives this error during conversion. How can I modify the code to resolve this error:</p>
  
  <pre><code>ValueError: row index was 65536, not allowed by .xls format
  </code></pre>
  
  <p>Also if i convert the text file to xlsx format it gives the same error</p>
  
  <p>Any guidance would be greatly appreciated.</p>
  
  <p>How do I edit the code to resolve this error?</p>
  
  <pre><code>import xlwt
  import io
  
  book = xlwt.Workbook()
  ws = book.add_sheet('First Sheet')  # Add a sheet
  
  with io.open("data.txt", mode="r", encoding="utf-8") as f:
  for row_idx, row in enumerate(f):
      row = row.rstrip()
  
   ws.write(row_idx, 0, row[0:8])
  .
  .
  .
    # and so on...
  
  book.save("excelfile.xls")# if i edit book.save("excelfile.xlxs") it gives the same error
  </code></pre>