请帮助解决Pycharm上的此错误。使用django

我试图使用Django创建一个网站,我的下一步是运行manage.py来创建超级用户,但是当我输入用户名、电子邮件地址、密码,然后按Enter键时,IDE(Pycharm)会反馈一个命令错误:

manage.py@education > createsuperuser
"D:\PyCharm 2019.1\bin\runnerw64.exe" E:\pythonproject\education\Scripts\python.exe "D:\PyCharm 2019.1\helpers\pycharm\django_manage.py" createsuperuser E:/pythonproject/education
Tracking file by folder pattern:  migrations
Username:  admin
Email address:  976413993@qq.com
Warning: Password input may be echoed.
Password:  12345678
Warning: Password input may be echoed.
Password (again):  12345678
This password is too common.
This password is entirely numeric.
Bypass password validation and create user anyway? [y/N]:  y
CommandError: '' value has an invalid date format. It must be in YYYY-MM-DD format.

这是用户配置文件:

# -*- encoding:utf-8 -*-
from django.db import models
from django.contrib.auth.models import AbstractUser
from datetime import datetime

# Create your models here.


class UserProfile(AbstractUser):
    nick_name = models.CharField(max_length=50, default="", verbose_name=u"昵称")
    birday = models.DateField(verbose_name=u"生日", default="")
    gender = models.CharField(choices=(("male", u"男"), ("female", u"女")), default="male", max_length=10)
    address = models.CharField(max_length=100, default=u"")
    mobile = models.CharField(max_length=11, null=True, blank=True)
    image = models.ImageField(upload_to="image/%Y/%m", default=u"image/default.png", max_length=100)

    class Meta:
        verbose_name = "用户信息"
        verbose_name_plural = verbose_name

    def __unicode__(self):
        return self.username


class EmailVerifyRecord(models.Model):
    code = models.CharField(max_length=20, verbose_name=u"验证码")
    email = models.EmailField(max_length=50, verbose_name=u"邮箱")
    send_type = models.CharField(choices=(("register", u"注册"), ("forget", u"找回密码")), max_length=10)
    send_time = models.DateTimeField(default=datetime.now)

    class Meta:
        verbose_name = u"邮箱验证码"
        verbose_name_plural = verbose_name


class Banner(models.Model):
    title = models.CharField(max_length=100, verbose_name=u"标题")
    image = models.ImageField(upload_to="banner/%Y/%m", verbose_name=u"轮播图", max_length=100)
    url = models.URLField(max_length=100, verbose_name=u"访问地址")
    index = models.IntegerField(default=100, verbose_name=u"顺序")
    add_time = models.DateTimeField(default=datetime.now, verbose_name=u"添加时间")

    class Meta:
        verbose_name = u"轮播图"
        verbose_name_plural = verbose_name

我试图用谷歌搜索这个问题,但没有找到任何有用的信息。