.xlsx和xls(最新版本)到pdf使用python

借助这个.doc到pdf使用python 链接我正在尝试使用excel(.xlsx和xls格式)

以下是修改的Excel代码:

import os
from win32com import client

folder = "C:\\Oprance\\Excel\\XlsxWriter-0.5.1"
file_type = 'xlsx'
out_folder = folder + "\\PDF_excel"

os.chdir(folder)

if not os.path.exists(out_folder):
    print 'Creating output folder...'
    os.makedirs(out_folder)
    print out_folder, 'created.'
else:
    print out_folder, 'already exists.\n'

for files in os.listdir("."):
    if files.endswith(".xlsx"):
        print files

print '\n\n'

word = client.DispatchEx("Excel.Application")
for files in os.listdir("."):
    if files.endswith(".xlsx") or files.endswith('xls'):
        out_name = files.replace(file_type, r"pdf")
        in_file = os.path.abspath(folder + "\\" + files)
        out_file = os.path.abspath(out_folder + "\\" + out_name)
        doc = word.Workbooks.Open(in_file)
        print 'Exporting', out_file
        doc.SaveAs(out_file, FileFormat=56)
        doc.Close()

它显示以下错误:

>>> execfile('excel_to_pdf.py')
Creating output folder...
C:\Excel\XlsxWriter-0.5.1\PDF_excel created.
apms_trial.xlsx
~$apms_trial.xlsx

Exporting C:\Excel\XlsxWriter-0.5.1\PDF_excel\apms_trial.pdf
Traceback (most recent call last):
  File "", line 1, in 
  File "excel_to_pdf.py", line 30, in 
    doc = word.Workbooks.Open(in_file)
  File ">", line 8, in Open
pywintypes.com_error: (-2147352567, 'Exception occurred.', (0, u'Microsoft Excel
', u"Excel cannot open the file '~$apms_trial.xlsx' because the file format or f
ile extension is not valid. Verify that the file has not been corrupted and that
 the file extension matches the format of the file.", u'xlmain11.chm', 0, -21468
27284), None)
>>>

有问题

doc.SaveAs(out_file,FileFormat = 56)

FileFormat文件格式应该是什么？请帮忙