field=models.CharField(error_messages={'unique':'A user with that username already exists.'},max_length=254,unique=True,validators=[django.core.validators.RegexValidator('^[\\w.+-]+$','Enter a valid username. This value may contain only letters, numbers and ./+/-/_ characters.')],help_text='Required. 254 characters or fewer. Letters, digits and ./+/-/_ only.',verbose_name='username'),