COULD NOT DISPLAY THAT PAGE.
                      HERE IS THE ERROR MESSAGE:
<br>'Category' object has no attribute 'modificationTime'

 - Expression: "item.editDateForSiteMap() if hasattr(item,'editDateForSiteMap') else '2020-07-02'"
 - Filename:   HomePage/sitemap.txt
 - Location:   (line 9: col 10)
 - Arguments:  context: <SiteRootPage ('syndicate',) at 0x808cc16d0>
               request: <Request ('None',) at 0x8096d73a0>
               view: <AceObjectIndex ('index',) at 0x80b482430>
               target_language: <NoneType ('None',) at 0x306940>
               repeat: <RepeatDict ('None',) at 0x80b482640>
               item: <Category ('european-winter-hot-spells',) at 0x812dcf5f0>