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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 select_site_view(self, request, form_url=''):
 """ Display a choice form to select which site to add settings. """

        if not self.has_add_permission(request):
            raise PermissionDenied

        extra_qs = ''
        if request.META['QUERY_STRING']:
            extra_qs = '&' + request.META['QUERY_STRING']

        site_choices = self.get_site_choices()

        if len(site_choices) == 1:
            return HttpResponseRedirect('?site_id={0}{1}'.format(site_choices[0][0], extra_qs))

        # Create form
        form = self.select_site_form(
            data=request.POST if request.method == 'POST' else None,
            initial={'site': site_choices[0][0]}
        )

        form.fields['site'].choices = site_choices

        if form.is_valid():
            return HttpResponseRedirect(
                '?site_id={0}{1}'.format(form.cleaned_data['site'], extra_qs))

        # Wrap in all admin layout
        fieldsets = ((None, {'fields': ('site',)}),)
        adminForm = AdminForm(form, fieldsets, {}, model_admin=self)
        media = self.media + adminForm.media

        context = {
            'title': _('Add %s') % force_text(self.opts.verbose_name),
            'adminform': adminForm,
            'is_popup': '_popup' in request.GET,
            'media': mark_safe(media),
            'errors': AdminErrorList(form, ()),
            'app_label': self.opts.app_label,
        }

        return self.render_select_site_form(request, context, form_url)