Merge branch 'migration-django-4-2' into 'main'

[Draft] nk20 v2.0.0 with django 4.2

See merge request bde/nk20!230

apps/member/forms.py

@@ -3,7 +3,7 @@
 
 import io
 
-from PIL import Image, ImageSequence
+from bootstrap_datepicker_plus.widgets import DatePickerInput
 from django import forms
 from django.conf import settings
 from django.contrib.auth.forms import AuthenticationForm
@@ -13,8 +13,9 @@ from django.forms import CheckboxSelectMultiple
 from django.utils import timezone
 from django.utils.translation import gettext_lazy as _
 from note.models import NoteSpecial, Alias
-from note_kfet.inputs import Autocomplete, AmountInput, DatePickerInput
+from note_kfet.inputs import Autocomplete, AmountInput
 from permission.models import PermissionMask, Role
+from PIL import Image, ImageSequence
 
 from .models import Profile, Club, Membership
 
@@ -32,7 +33,7 @@ class UserForm(forms.ModelForm):
         # Django usernames can only contain letters, numbers, @, ., +, - and _.
         # We want to allow users to have uncommon and unpractical usernames:
         # That is their problem, and we have normalized aliases for us.
-        return super()._get_validation_exclusions() + ["username"]
+        return super()._get_validation_exclusions() | {"username"}
 
     class Meta:
         model = User