老師您好? 請教一個問題

我自定義admin用戶模型，在創建超級用戶的時候報錯：?'Manager' object has no attribute 'get_by_natural_key'

環境：

python v3.7.5

django v2.2.4

# models.py

from?django.db?import?models
from?django.contrib.auth.models?import?AbstractBaseUser

class?UserProfile(AbstractBaseUser):
????identifier?=?models.CharField(max_length=40,?unique=True)
????USERNAME_FIELD?=?'identifier'????
????
????nick_name?=?models.CharField(max_length=50,?verbose_name='昵稱',?default='')????
????birday?=?models.DateField(verbose_name='生日',?null=True,?blank=True)????
????gender?=?models.CharField(max_length=10,?choices=(('male',?'男'),?('female',?'女')),?default='female')????
????address?=?models.CharField(max_length=100,?default='')????
????mobile?=?models.CharField(max_length=11,?null=True,?blank=True)????
????image?=?models.ImageField(upload_to='image/%Y/%m',?default='image/default.png',?max_length=100)????????
????
????class?Meta:????????
????????verbose_name?=?'用戶信息'????????
????????verbose_name_plural?=?verbose_name