You can check if a PO file is valid with the following command:

        msgfmt -c -o /dev/null <po file>
      

The following errors were found in python-django 's PO files:

gettext: django/conf/locale/sr_Latn/LC_MESSAGES/django.po: can't guess language
gettext: django/conf/locale/zh_Hans/LC_MESSAGES/django.po: can't guess language
gettext: django/conf/locale/zh_Hant/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/admin/locale/sr_Latn/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/admin/locale/sr_Latn/LC_MESSAGES/djangojs.po: can't guess language
gettext: django/contrib/admin/locale/zh_Hans/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/admin/locale/zh_Hans/LC_MESSAGES/djangojs.po: can't guess language
gettext: django/contrib/admin/locale/zh_Hant/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/admin/locale/zh_Hant/LC_MESSAGES/djangojs.po: can't guess language
gettext: django/contrib/admindocs/locale/sr_Latn/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/admindocs/locale/zh_Hans/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/admindocs/locale/zh_Hant/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/auth/locale/sr_Latn/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/auth/locale/zh_Hans/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/auth/locale/zh_Hant/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/contenttypes/locale/sr_Latn/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/contenttypes/locale/zh_Hans/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/contenttypes/locale/zh_Hant/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/flatpages/locale/sr_Latn/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/flatpages/locale/zh_Hans/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/flatpages/locale/zh_Hant/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/gis/locale/sr_Latn/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/gis/locale/zh_Hans/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/gis/locale/zh_Hant/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/humanize/locale/sr_Latn/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/humanize/locale/zh_Hans/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/humanize/locale/zh_Hant/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/postgres/locale/sr_Latn/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/postgres/locale/zh_Hans/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/postgres/locale/zh_Hant/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/redirects/locale/sr_Latn/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/redirects/locale/zh_Hans/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/redirects/locale/zh_Hant/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/sessions/locale/sr_Latn/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/sessions/locale/zh_Hans/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/sessions/locale/zh_Hant/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/sites/locale/sr_Latn/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/sites/locale/zh_Hans/LC_MESSAGES/django.po: can't guess language
gettext: django/contrib/sites/locale/zh_Hant/LC_MESSAGES/django.po: can't guess language
      

Please ask the translator (identified by the Last-Translator field in the PO file), the language team (identified by the Language-Team field) or debian-i18n for a fix.