如何做小写的xl单元格值+一些内容/某些内容＆＃39 ;?

Question

这是我的功能。我必须降低newfilename..i.e newfilename.lower（）

中的内容

def my_function(start, end):
    sheetname = 'my-sheet'
    filepath = "/myxl.xlsx"

try:
    work_book=xlrd.open_workbook(filepath)
except:
    print 'error'

try:
    worksheet = work_book.sheet_by_name(sheetname)
except:
    print 'error'

rows=worksheet.nrows
cols=worksheet.ncols

success = []
fail = []
for row in xrange(start,end):
    print "row no.       : ",row

    state = '/home/myfolder/'
    if os.path.exists(state):
        print "state folder exits"
    else:
        os.makedirs(state)

    district =  state + worksheet.cell_value(row,0) + '/'    
    if os.path.exists(district):
        print "district folder exits"
    else:
        os.makedirs(district)

    city = district +  worksheet.cell_value(row,2) + '/'
    if os.path.exists(city):
        print "city folder exits"
    else:
        os.makedirs(city)

    newfilename = city + worksheet.cell_value(row,4).replace (" ", "-") + '.png'
    if worksheet.cell_value(row,5) !="":
        oldfilename = worksheet.cell_value(row,5)
    else:
        oldfilename="no-image"

    newfullpath = newfilename
    oldfullpath = '/home/old/folder/' + oldfilename

    try:
        os.rename(oldfullpath,newfullpath)
        success.append(row)
    except Exception as e:
        fail.append(row)
        print "Error",e
    print 'renaming done for row #' ,row , ' file ', oldfilename , ' to ', newfilename

print 'SUCCESS ', success
print 'FAIL ', fail

newfilename.lower（）无法正常工作

这时我将使用unicode错误来... UnicodeEncodeError：＆＃39; ascii＆＃39;编解码器不能编码字符u＆＃39; \ u2019＆＃39;位置72：序数不在范围内（128）