title: xlwt set style making error: More than 4094 XFs (styles)
body: <p>I use Xlwt for writing an excel file. it's cells has some style (color, alignment ,borders ,  ... )</p>
  
  <p>when i use XFStyle and set borders and other attr of style, in some cases it make error:
  More than 4094 XFs (styles)</p>
  
  <p>why?
  what should i do with this error?</p>
  
  <p>thanks</p>