text: from django.conf import settings
  from django.contrib import admin, messages
  from django.contrib.admin.options import IS_POPUP_VAR
  from django.contrib.admin.utils import unquote
  from django.contrib.auth import update_session_auth_hash
  from django.contrib.auth.forms import (
      AdminPasswordChangeForm, UserChangeForm, UserCreationForm,
  )
  from django.contrib.auth.models import Group, User
  from django.core.exceptions import PermissionDenied
  from django.db import router, transaction
  from django.http import Http404, HttpResponseRedirect
  from django.template.response import TemplateResponse
  from django.urls import path, reverse
  from django.utils.decorators import method_decorator
  from django.utils.html import escape
  from django.utils.translation import gettext, gettext_lazy as _
  from django.views.decorators.csrf import csrf_protect
  from django.views.decorators.debug import sensitive_post_parameters
  
  csrf_protect_m = method_decorator(csrf_protect)
  sensitive_post_parameters_m = method_decorator(sensitive_post_parameters())
  
  
  @admin.register(Group)
  class GroupAdmin(admin.ModelAdmin):
      search_fields = ('name',)
      ordering = ('name',)
      filter_horizontal = ('permissions',)
  
      def formfield_for_manytomany(self, db_field, request=None, **kwargs):
          if db_field.name == 'permissions':
              qs = kwargs.get('queryset', db_field.remote_field.model.objects)
              # Avoid a major performance hit resolving permission names which
              # triggers a content_type load:
              kwargs['queryset'] = qs.select_related('content_type')
          return super().formfield_for_manytomany(db_field, request=request, **kwargs)
  
  
  @admin.register(User)
  class UserAdmin(admin.ModelAdmin):
      add_form_template = 'admin/auth/user/add_form.html'
      change_user_password_template = None
      fieldsets = (
          (None, {'fields': ('username', 'password')}),
          (_('Personal info'), {'fields': ('first_name', 'last_name', 'email')}),
          (_('Permissions'), {'fields': ('is_active', 'is_staff', 'is_superuser',
                                         'groups', 'user_permissions')}),
          (_('Important dates'), {'fields': ('last_login', 'date_joined')}),
      )
      add_fieldsets = (
          (None, {
              'classes': ('wide',),
              'fields': ('username', 'password1', 'password2'),
          }),
      )
      form = UserChangeForm
      add_form = UserCreationForm
      change_password_form = AdminPasswordChangeForm
      list_display = ('username', 'email', 'first_name', 'last_name', 'is_staff')
      list_filter = ('is_staff', 'is_superuser', 'is_active', 'groups')
      search_fields = ('username', 'first_name', 'last_name', 'email')
      ordering = ('username',)
      filter_horizontal = ('groups', 'user_permissions',)
  
      def get_fieldsets(self, request, obj=None):
          if not obj:
              return self.add_fieldsets
          return super().get_fieldsets(request, obj)
  
      def get_form(self, request, obj=None, **kwargs):
          """
          Use special form during user creation
          """
          defaults = {}
          if obj is None:
              defaults['form'] = self.add_form
          defaults.update(kwargs)
          return super().get_form(request, obj, **defaults)
  
      def get_urls(self):
          return [
              path(
                  '<id>/password/',
                  self.admin_site.admin_view(self.user_change_password),
                  name='auth_user_password_change',
              ),
          ] + super().get_urls()
  
      def lookup_allowed(self, lookup, value):
          # See #20078: we don't want to allow any lookups involving passwords.
          if lookup.startswith('password'):
              return False
          return super().lookup_allowed(lookup, value)
  
      @sensitive_post_parameters_m
      @csrf_protect_m
      def add_view(self, request, form_url='', extra_context=None):
          with transaction.atomic(using=router.db_for_write(self.model)):
              return self._add_view(request, form_url, extra_context)
  
      def _add_view(self, request, form_url='', extra_context=None):
          # It's an error for a user to have add permission but NOT change
          # permission for users. If we allowed such users to add users, they
          # could create superusers, which would mean they would essentially have
          # the permission to change users. To avoid the problem entirely, we
          # disallow users from adding users if they don't have change
          # permission.
          if not self.has_change_permission(request):
              if self.has_add_permission(request) and settings.DEBUG:
                  # Raise Http404 in debug mode so that the user gets a helpful
                  # error message.
                  raise Http404(
                      'Your user does not have the "Change user" permission. In '
                      'order to add users, Django requires that your user '
                      'account have both the "Add user" and "Change user" '
                      'permissions set.')
              raise PermissionDenied
          if extra_context is None:
              extra_context = {}
          username_field = self.model._meta.get_field(self.model.USERNAME_FIELD)
          defaults = {
              'auto_populated_fields': (),
              'username_help_text': username_field.help_text,
          }
          extra_context.update(defaults)
          return super().add_view(request, form_url, extra_context)
  
      @sensitive_post_parameters_m
      def user_change_password(self, request, id, form_url=''):
          if not self.has_change_permission(request):
              raise PermissionDenied
          user = self.get_object(request, unquote(id))
          if user is None:
              raise Http404(_('%(name)s object with primary key %(key)r does not exist.') % {
                  'name': self.model._meta.verbose_name,
                  'key': escape(id),
              })
          if request.method == 'POST':
              form = self.change_password_form(user, request.POST)
              if form.is_valid():
                  form.save()
                  change_message = self.construct_change_message(request, form, None)
                  self.log_change(request, user, change_message)
                  msg = gettext('Password changed successfully.')
                  messages.success(request, msg)
                  update_session_auth_hash(request, form.user)
                  return HttpResponseRedirect(
                      reverse(
                          '%s:%s_%s_change' % (
                              self.admin_site.name,
                              user._meta.app_label,
                              user._meta.model_name,
                          ),
                          args=(user.pk,),
                      )
                  )
          else:
              form = self.change_password_form(user)
  
          fieldsets = [(None, {'fields': list(form.base_fields)})]
          adminForm = admin.helpers.AdminForm(form, fieldsets, {})
  
          context = {
              'title': _('Change password: %s') % escape(user.get_username()),
              'adminForm': adminForm,
              'form_url': form_url,
              'form': form,
              'is_popup': (IS_POPUP_VAR in request.POST or
                           IS_POPUP_VAR in request.GET),
              'add': True,
              'change': False,
              'has_delete_permission': False,
              'has_change_permission': True,
              'has_absolute_url': False,
              'opts': self.model._meta,
              'original': user,
              'save_as': False,
              'show_save': True,
              **self.admin_site.each_context(request),
          }
  
          request.current_app = self.admin_site.name
  
          return TemplateResponse(
              request,
              self.change_user_password_template or
              'admin/auth/user/change_password.html',
              context,
          )
  
      def response_add(self, request, obj, post_url_continue=None):
          """
          Determine the HttpResponse for the add_view stage. It mostly defers to
          its superclass implementation but is customized because the User model
          has a slightly different workflow.
          """
          # We should allow further modification of the user just added i.e. the
          # 'Save' button should behave like the 'Save and continue editing'
          # button except in two scenarios:
          # * The user has pressed the 'Save and add another' button
          # * We are adding a user in a popup
          if '_addanother' not in request.POST and IS_POPUP_VAR not in request.POST:
              request.POST = request.POST.copy()
              request.POST['_continue'] = 1
          return super().response_add(request, obj, post_url_continue)
  