workaround for the python xlrd error

Just comment the below line in the file compdoc.py:

if self.seen[s]:
    print("_locate_stream(%s): seen" % qname, file=self.logfile);dump_list(self.seen, 20, self.logfile)
    raise CompDocError("%s corruption: seen[%d] == %d" % (qname, s, self.seen[s]))


From: http://stackoverflow.com/questions/12705527/reading-excel-files-with-xlrd