[py3] Fixed contrib.auth tests

    default_username = get_system_username()

    try:

        default_username = unicodedata.normalize('NFKD', default_username)\

            .encode('ascii', 'ignore').replace(' ', '').lower()

            .encode('ascii', 'ignore').decode('ascii').replace(' ', '').lower()

    except UnicodeDecodeError:

        return ''

    if not RE_VALID_USERNAME.match(default_username):

import sys

from datetime import date, timedelta

from django.conf import settings

from django.contrib.auth.models import User

from django.contrib.auth.tokens import PasswordResetTokenGenerator

from django.test import TestCase

from django.utils import unittest

class TokenGeneratorTest(TestCase):

        p2 = Mocked(date.today() + timedelta(settings.PASSWORD_RESET_TIMEOUT_DAYS + 1))

        self.assertFalse(p2.check_token(user, tk1))

    @unittest.skipIf(sys.version_info[:2] >= (3, 0), "Unnecessary test with Python 3")

    def test_date_length(self):

        """

        Make sure we don't allow overly long dates, causing a potential DoS.

    try:

        uid_int = base36_to_int(uidb36)

        user = User.objects.get(id=uid_int)

    except (ValueError, User.DoesNotExist):

    except (ValueError, OverflowError, User.DoesNotExist):

        user = None

    if user is not None and token_generator.check_token(user, token):