title: 'User' object has no attribute 'get_all_permissions'
body: <ul>
  <li><p>What is the cause of this error? I got this error after changing the
  admin style 'User' object has no attribute 'get_all_permissions'  plz help me. (What is the cause of this error? I got this error after changing the
  admin style 'User' object has no attribute 'get_all_permissions'  plz help me. )</p>
  <pre><code> class UserManager(BaseUserManager):
          def create_user(self, email, username, full_name, phone, password):
              if not email:
                  raise ValueError('plz input email')
              if not username:
                  raise ValueError('plz input username')
              if not full_name:
                  raise ValueError('plz input full_name')
              if not phone:
                  raise ValueError('plz input phone')
  
              user = self.model(email=self.normalize_email(email), username=username, full_name=full_name, phone=phone)
              user.set_password(password)
              user.save(using=self._db)
              return user
  
          def create_superuser(self, email, username, full_name, phone, password):
              user = self.create_user(email, username, full_name, phone, password)
              user.is_admin = True
              user.is_superuser = True
              user.save(using=self._db)
              return user
  
  
      class User(AbstractBaseUser):
          email = models.EmailField(max_length=50, unique=True)
          username = models.CharField(max_length=100, null=True, blank=True, unique=True)
          full_name = models.CharField(max_length=300)
          phone = models.CharField(max_length=15)
          address = models.CharField(max_length=500)
          is_admin = models.BooleanField(default=False)
          is_active = models.BooleanField(default=True)
          is_superuser = models.BooleanField(default=False)
          permission = models.ManyToManyField(Permission, related_name='users')
          USERNAME_FIELD = 'email'
          REQUIRED_FIELDS = ['username', 'full_name', 'phone']
          objects = UserManager()
  
          def __str__(self):
              return self.email
  
          def has_perm(self, perm, obj=None):
              return self.is_superuser
  
          def has_module_perms(self, app_label):
              return self.is_superuser
  
          @property
          def is_staff(self):
              return self.is_admin
  </code></pre>
  </li>
  </ul>