Validating models...

Unhandled exception in thread started by <function check_errors.<locals>.wrapper at 0x014CA588>
Traceback (most recent call last):
  File "C:\workspace\03-src\lib\site-packages\django\utils\autoreload.py", line 93, in wrapper
    fn(*args, **kwargs)
  File "C:\workspace\03-src\lib\site-packages\django\core\management\commands\runserver.py", line 101, in
inner_run
    self.validate(display_num_errors=True)
  File "C:\workspace\03-src\lib\site-packages\django\core\management\base.py", line 310, in validate
    num_errors = get_validation_errors(s, app)
  File "C:\workspace\03-src\lib\site-packages\django\core\management\validation.py", line 34, in get_valid
ation_errors
    for (app_name, error) in get_app_errors().items():
  File "C:\workspace\03-src\lib\site-packages\django\db\models\loading.py", line 196, in get_app_errors
    self._populate()
  File "C:\workspace\03-src\lib\site-packages\django\db\models\loading.py", line 75, in _populate
    self.load_app(app_name, True)
  File "C:\workspace\03-src\lib\site-packages\django\db\models\loading.py", line 99, in load_app
    models = import_module('%s.models' % app_name)
  File "C:\workspace\03-src\lib\importlib\__init__.py", line 109, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 2254, in _gcd_import
  File "<frozen importlib._bootstrap>", line 2237, in _find_and_load
  File "<frozen importlib._bootstrap>", line 2226, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 1200, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 1129, in _exec
  File "<frozen importlib._bootstrap>", line 1471, in exec_module
  File "<frozen importlib._bootstrap>", line 321, in _call_with_frames_removed
  File "C:\workspace\03-src\djangoproject\service\models.py", line 34, in <module>
    class Vehicle(models.Model):
  File "C:\workspace\03-src\djangoproject\service\models.py", line 45, in Vehicle
    auto_choose=True
  File "C:\workspace\03-src\lib\site-packages\smart_selects\db_fields.py", line 20, in __init__
    if isinstance(to, basestring):
NameError: name 'basestring' is not defined