xlwt.write accept style informations as its third argument. Unfortunately, xlrd and xlwt use two very different XF object format. So you cannot directly copy the cell's style from the workbook read by xlrd to the workbook created by xlwt. The workaround is the use an xlutils.XLWTWriter to copy the file,...
A set is going to give you an unordered collection of unique values. If you have duplicate cells in your spreadsheet, only the first one will be added to the set, the rest will be discarded. Based on your comments, it sounds like you're just doing some debugging, but if...
Thats the default xlwt behavior, you can either override that with sheet = book.add_sheet('Sheet1', cell_overwrite_ok=True) (taken from this answer) That will only overwrite the original value Put me, though. You'll have to merge the values manually, like this: from cStringIO import StringIO sheet = book.add_sheet('Sheet1') buf = StringIO() buf.write('Put me')...
xlrd will load your worksheet file into memory at the time you call the open_workbook() method. Any changes made to the worksheet file after you call open_workbook() are not automatically reflected in the object in memory. If you take a look at the xlrd source code on Github, in particular...