import xlrd       def open_excel(fileName="simple.xls"):          try:              fileHandler = xlrd.open_workbook(fileName)              return fileHandler          except Exception, e:              print str(e)          def scan_excel(sheet_name1=u'Sheet1'):          handler = open_excel()          page = handler.sheet_by_name(sheet_name1)          return page      def trim_cols(index=0):          page = scan_excel()          col1 = page.col_values(index)          col2 = []          for item in col1:              if item not in col2:                  col2.append(item)          print col1          print col2      def main():          trim_cols()      if __name__ == "__main__":          main()