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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def landing_view(request):
    ''' The external landing.'''
    revision = None
    can_edit = False
    edit_url = None

    if "farnswiki" in settings.INSTALLED_APPS:
        from wiki.models import Page
        from wiki.hooks import hookset
        binder = settings.WIKI_BINDERS[0]
        wiki = binder.lookup()
        try:
            if wiki:
                page = wiki.pages.get(slug="landing")
            else:
                page = Page.objects.get(slug="landing")
        except (Page.DoesNotExist, Page.MultipleObjectsReturned):
            can_edit = hookset.can_create_page(wiki, request.user, slug="landing")
            edit_url = binder.page_url(wiki, "landing")
        else:
            revision = page.revisions.latest()
            can_edit = hookset.can_edit_page(page, request.user)
            edit_url = page.get_edit_url()

    return render_to_response('external.html', {
        "page_name": "Landing",
        "revision": revision,
        "can_edit": can_edit,
        "edit_url": edit_url,
        }, context_instance=RequestContext(request))