text: from django.contrib.auth.models import AbstractUser
  from django.core.validators import MinLengthValidator
  from django.db import models
  from django.utils.translation import ugettext_lazy as _
  
  
  class User(AbstractUser):
      username = models.CharField(
          _('username'), unique=True, max_length=50,
          validators=[MinLengthValidator(2), ])
      password = models.CharField(_('password'), max_length=128)
      email = models.EmailField(_('email address'), unique=True)
      first_name = models.CharField(max_length=50, blank=True)
      last_name = models.CharField(max_length=50, blank=True)
  