title: decrypt excel files
body: <p>Hi I have 1000 encrypted workbooks which I would like to decrypt by providing a pwd.
  I could not find a decrypt method under apache poi or python's xlrd module.</p>
  
  <p>Does anyone know a library which could handle this (<code>wbc.decrypt(pwd)</code>). I would prefer a lib i could you use from a unix box.</p>
  
  <p>Thanks</p>