对这些.xls文件的格式感到非常困惑，因为它们不是真正的.xls文件，我把文件的前几行放在下面供参考，完整的文件放在这里。
转换普通.xls对p.save_book_as(file_name=fname, dest_file_name=fname+'x')没有问题。
我想用python批量转换为.xlsx，用下面的格式也可以吗？
MIME-Version: 1.0
X-Document-Type: Workbook
Content-Type: multipart/related; boundary="----=_NextPart_86ab7b61_9054_45ca_a3a6_49bc8ebc61db"
This document is a Single File Web Page, also known as a Web Archive file. If you are seeing this message, your browser or editor doesn't support Web Archive files. Please download a browser that supports Web Archive, such as Microsoft Internet Explorer.
------=_NextPart_86ab7b61_9054_45ca_a3a6_49bc8ebc61db
Content-Location: file:///C:/86ab7b61_9054_45ca_a3a6_49bc8ebc61db/Workbook.html
Content-Transfer-Encoding: quoted-printable
Content-Type: text/html; charset="us-ascii"
<html xmlns:v=3D"urn:schemas-microsoft-com:vml" xmlns:o=3D"urn:schemas-microsoft-com:office:office" xmlns:x=3D"urn:schemas-microsoft-com:office:excel" xmlns=3D"http://www.w3.org/TR/REC-html40">
<head>
<meta name=3D"Excel Workbook Frameset">
<meta name=3DProgId content=3DExcel.Sheet>
<link rel=3DFile-List href=3D"Worksheets/filelist.xml">
<!--[if gte mso 9]><xml>
<x:ExcelWorkbook>
<x:ExcelWorksheets>
<x:ExcelWorksheet>
这似乎是"Excel兼容HTML"；。虽然我不知道纯python转换器，但你可以尝试使用excel作为外部转换器，即打开这些文件并将其保存到xlsx中，如下所述并复制到下面。这需要pywin32软件包才能远程访问excel。
import win32com.client as win32
fname = "full+path+to+xls_file"
excel = win32.gencache.EnsureDispatch('Excel.Application')
wb = excel.Workbooks.Open(fname)
wb.SaveAs(fname+"x", FileFormat = 51) #FileFormat = 51 is for .xlsx extension
wb.Close() #FileFormat = 56 is for .xls extension
excel.Application.Quit()