import win32com.client
xlApp = win32com.client.Dispatch("Excel.Application")
xlApp.Visible=1
workBook = xlApp.Workbooks.Open(r"C:MyTest.xls")
print str(workBook.ActiveSheet.Cells(i,1))
workBook.ActiveSheet.Cells(1, 1).Value = "hello"
workBook.Close(SaveChanges=0)
xlApp.Quit()