Fixed #25224 -- Fixed typo in docs/ref/contrib/flatpages.txt

    If you add or modify flatpages via your own code, you will likely want to

    check for duplicate flatpage URLs within the same site. The flatpage form

    used in the admin performs this validation check, and can be imported from

    ``django.contrib.flatpages.forms.FlatPageForm`` and used in your own

    ``django.contrib.flatpages.forms.FlatpageForm`` and used in your own

    views.

Flatpage templates