'Creates a User with the given username, email and password'

def create_user(self, email, password=None, is_staff=False, is_active=True, username=u'', **extra_fields):

    email = UserManager.normalize_email(email)
    user = self.model(email=email, is_active=is_active, is_staff=is_staff, **extra_fields)
    if password:
        user.set_password(password)
    user.save()
    return user
