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djangotoolbox / djangotoolbox / admin.py

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from django import forms
from django.contrib import admin
from django.contrib.auth.admin import UserAdmin
from django.contrib.auth.models import User, Group

class UserForm(forms.ModelForm):
    class Meta:
        model = User
        fields = ('username', 'email', 'first_name', 'last_name', 'is_active',
                  'is_staff', 'is_superuser')

class CustomUserAdmin(UserAdmin):
    fieldsets = None
    form = UserForm
    search_fields = ('=username',)

admin.site.unregister(User)
admin.site.unregister(Group)
admin.site.register(User, CustomUserAdmin)