今晚看了下auth/auth，看了下docs，发现红色部分应该是个失误吧，email不是required的，因为
在AbstractUser class中的email = models.EmailField(_('email address'), blank=True)blank=True可以看出
class AbstractUser(AbstractBaseUser, PermissionsMixin):
"""
An abstract base class implementing a fully featured User model with
admin-compliant permissions.
Username, password and email are required. Other fields are optional.
"""
username = models.CharField(_('username'), max_length=30, unique=True,
help_text=_('Required. 30 characters or fewer. Letters, numbers and '
'@/./+/-/_ characters'),
validators=[
validators.RegexValidator(re.compile('^[\w.@+-]+$'), _('Enter a valid username.'), 'invalid')
])
first_name = models.CharField(_('first name'), max_length=30, blank=True)
last_name = models.CharField(_('last name'), max_length=30, blank=True)
email = models.EmailField(_('email address'), blank=True)
is_staff = models.BooleanField(_('staff status'), default=False,
help_text=_('Designates whether the user can log into this admin '
'site.'))
is_active = models.BooleanField(_('active'), default=True,
help_text=_('Designates whether this user should be treated as '
'active. Unselect this instead of deleting accounts.'))
date_joined = models.DateTimeField(_('date joined'), default=timezone.now)
objects = UserManager()
class User(AbstractUser):
"""
Users within the Django authentication system are represented by this
model.
Username, password and
email are required. Other fields are optional.
"""
class Meta:
swappable = 'AUTH_USER_MODEL'
