@csrf_protect_m
    def changelist_view(self, request, extra_context=None):
        """
        The 'change list' admin view for this model.
        """
        from django.contrib.admin.views.main import ERROR_FLAG
        opts = self.model._meta
        app_label = opts.app_label
        if not self.has_change_permission(request, None):
            raise PermissionDenied

        list_display = self.get_list_display(request)
        list_display_links = self.get_list_display_links(request, list_display)
        list_filter = self.get_list_filter(request)
        search_fields = self.get_search_fields(request)
        list_select_related = self.get_list_select_related(request)

        # Check actions to see if any are available on this changelist
        actions = self.get_actions(request)
        if actions:
            # Add the action checkboxes if there are any actions available.
            list_display = ['action_checkbox'] + list(list_display)

        ChangeList = self.get_changelist(request)
        try:
            cl = ChangeList(
                request, self.model, list_display,
                list_display_links, list_filter, self.date_hierarchy,
                search_fields, list_select_related, self.list_per_page,
                self.list_max_show_all, self.list_editable, self,
            )
        except IncorrectLookupParameters:
            # Wacky lookup parameters were given, so redirect to the main
            # changelist page, without parameters, and pass an 'invalid=1'
            # parameter via the query string. If wacky parameters were given
            # and the 'invalid=1' parameter was already in the query string,
            # something is screwed up with the database, so display an error
            # page.
            if ERROR_FLAG in request.GET.keys():
                return SimpleTemplateResponse('admin/invalid_setup.html', {
                    'title': _('Database error'),
                })
            return HttpResponseRedirect(request.path + '?' + ERROR_FLAG + '=1')

        # If the request was POSTed, this might be a bulk action or a bulk
        # edit. Try to look up an action or confirmation first, but if this
        # isn't an action the POST will fall through to the bulk edit check,
        # below.
        action_failed = False
        selected = request.POST.getlist(helpers.ACTION_CHECKBOX_NAME)

        # Actions with no confirmation
        if (actions and request.method == 'POST' and
                'index' in request.POST and '_save' not in request.POST):
            if selected:
                response = self.response_action(request, queryset=cl.get_queryset(request))
                if response:
                    return response
                else:
                    action_failed = True
            else:
                msg = _("Items must be selected in order to perform "
                        "actions on them. No items have been changed.")
                self.message_user(request, msg, messages.WARNING)
                action_failed = True

        # Actions with confirmation
        if (actions and request.method == 'POST' and
                helpers.ACTION_CHECKBOX_NAME in request.POST and
                'index' not in request.POST and request.POST not in '_save'):
            if selected:
                response = self.response_action(request, queryset=cl.get_queryset(request))
                if response:
                    return response
                else:
                    action_failed = True

        # If we're allowing changelist editing, we need to construct a formset
        # for the changelist given all the fields to be edited. Then we'll
        # use the formset to validate/process POSTed data.
        formset = cl.formset = None

        # Handle POSTed bulk-edit data.
        if (request.method == "POST" and cl.list_editable and
                '_save' in request.POST and not action_failed):
            FormSet = self.get_changelist_formset(request)
            formset = cl.formset = FormSet(request.POST, request.FILES, queryset=self.get_queryset(request))
            if formset.is_valid():
                changecount = 0
                for form in formset.forms:
                    if form.has_changed():
                        obj = self.save_form(request, form, change=True)
                        self.save_model(request, obj, form, change=True)
                        self.save_related(request, form, formsets=[], change=True)
                        change_msg = self.construct_change_message(request, form, None)
                        self.log_change(request, obj, change_msg)
                        changecount += 1

                if changecount:
                    if changecount == 1:
                        name = force_text(opts.verbose_name)
                    else:
                        name = force_text(opts.verbose_name_plural)
                    msg = ungettext(
                        "%(count)s %(name)s was changed successfully.",
                        "%(count)s %(name)s were changed successfully.",
                        changecount
                    ) % {
                        'count': changecount,
                        'name': name,
                        'obj': force_text(obj),
                    }
                    self.message_user(request, msg, messages.SUCCESS)

                return HttpResponseRedirect(request.get_full_path())

        # Handle GET -- construct a formset for display.
        elif cl.list_editable:
            FormSet = self.get_changelist_formset(request)
            formset = cl.formset = FormSet(queryset=cl.result_list)

        # Build the list of media to be used by the formset.
        if formset:
            media = self.media + formset.media
        else:
            media = self.media

        # Build the action form and populate it with available actions.
        if actions:
            action_form = self.action_form(auto_id=None)
            action_form.fields['action'].choices = self.get_action_choices(request)
        else:
            action_form = None

        selection_note_all = ungettext(
            '%(total_count)s selected',
            'All %(total_count)s selected',
            cl.result_count
        )

        context = dict(
            self.admin_site.each_context(request),
            module_name=force_text(opts.verbose_name_plural),
            selection_note=_('0 of %(cnt)s selected') % {'cnt': len(cl.result_list)},
            selection_note_all=selection_note_all % {'total_count': cl.result_count},
            title=cl.title,
            is_popup=cl.is_popup,
            to_field=cl.to_field,
            cl=cl,
            media=media,
            has_add_permission=self.has_add_permission(request),
            opts=cl.opts,
            action_form=action_form,
            actions_on_top=self.actions_on_top,
            actions_on_bottom=self.actions_on_bottom,
            actions_selection_counter=self.actions_selection_counter,
            preserved_filters=self.get_preserved_filters(request),
        )
        context.update(extra_context or {})

        request.current_app = self.admin_site.name

        return TemplateResponse(request, self.change_list_template or [
            'admin/%s/%s/change_list.html' % (app_label, opts.model_name),
            'admin/%s/change_list.html' % app_label,
            'admin/change_list.html'
        ], context)
dataset/ETHPy150Open django/django/django/contrib/admin/options.py/ModelAdmin.changelist_view/swapped operands of `not in`