python - Creating a custom profile with "column username is not unique error" -

i'm trying extend basic user profile in django-allauth. signup form loads correctly, after submitting form there's "column username not unique error".

the project files below:

models.py

from django.db import models django.contrib.auth.models import user  # create models here. class userprofile(models.model):      user = models.onetoonefield(user, related_name='userprofile')      # additional attributes wish include.     website = models.urlfield(blank=true)     picture = models.imagefield(upload_to='profile_images', blank=true)     has_accepted_tos = models.booleanfield(default=false,                                             verbose_name='i accept site rules')     #required_fields = ['has_accepted_tos']      def __unicode__(self):         return self.user.username      user.profile = property(lambda u:userprofile.objects.get_or_create(user=u)[0]) 

forms.py

from django.contrib.auth import get_user_model .models import userprofile django.forms import charfield, booleanfield, modelform django.utils.translation import ugettext _ allauth.account.adapter import get_adapter  # forms.py      class signupform(modelform):          has_accepted_tos = booleanfield(error_messages={'required': _('you must accept terms , conditions')},                                              label=_('i accept site terms , conditions'),                                              required=true)          class meta:             #model = get_user_model             model = userprofile             fields = ('website', 'picture', 'has_accepted_tos')           def signup(self, request, user):             adapter = get_adapter()             user = adapter.new_user(request)             adapter.save_user(request, user, self) 

i'm suspecting signup method not implemented correctly. can advise?