CREATE TABLE `test_suite` (
  `team_name` varchar(30) NOT NULL,
  `suite_name` varchar(100) NOT NULL,
  `description` varchar(200) DEFAULT NULL,
  `schedule` varchar(100) DEFAULT NULL,
  `email_list_ok` varchar(200) DEFAULT NULL,
  `email_list_fail` varchar(200) DEFAULT NULL,
  `template_name` varchar(100) NOT NULL,
  PRIMARY KEY (`team_name`,`suite_name`),
  KEY `fk_test_suite__email_templates` (`template_name`),
  CONSTRAINT `fk_test_suite__email_templates` FOREIGN KEY (`template_name`) REFERENCES `email_templates` (`template_name`),
  CONSTRAINT `fk_test_suite__team` FOREIGN KEY (`team_name`) REFERENCES `team` (`team_name`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

class Team(models.Model):
    team_name = models.CharField(primary_key=True, max_length=30)
    description = models.CharField(max_length=100, blank=True, null=True)

    class Meta:
        managed = False
        db_table = 'team'

class TestSuite(models.Model):
    team_name = models.ForeignKey(Team, on_delete=models.DO_NOTHING, db_column='team_name')
    suite_name = models.CharField(max_length=100)
    description = models.CharField(max_length=200, blank=True, null=True)
    schedule = models.CharField(max_length=100, blank=True, null=True)
    email_list_ok = models.CharField(max_length=200, blank=True, null=True)
    email_list_fail = models.CharField(max_length=200, blank=True, null=True)
    template_name = models.ForeignKey(EmailTemplates, on_delete=models.DO_NOTHING, db_column='template_name')

    class Meta:
        managed = False
        db_table = 'test_suite'
        unique_together = (('team_name', 'suite_name'),)

class TestSuiteViewSet(viewsets.ModelViewSet):
    queryset = models.TestSuite.objects.values('team_name','suite_name', 'description','schedule','email_list_ok','email_list_fail','template_name')
    serializer_class = serializers.TestSuiteSerializer

class TeamViewSet(viewsets.ModelViewSet):
    queryset = models.Team.objects.all()
    serializer_class = serializers.TeamSerializer

class TestSuiteSerializer(serializers.ModelSerializer):
    class Meta:
        model = models.TestSuite
        fields = ['team_name','suite_name', 'description','schedule','email_list_ok','email_list_fail','template_name']

File "/usr/local/lib/python3.6/dist-packages/django/core/handlers/exception.py" in inner
  35.             response = get_response(request)

File "/usr/local/lib/python3.6/dist-packages/django/core/handlers/base.py" in _get_response
  128.                 response = self.process_exception_by_middleware(e, request)

File "/usr/local/lib/python3.6/dist-packages/django/core/handlers/base.py" in _get_response
  126.                 response = wrapped_callback(request, *callback_args, **callback_kwargs)

File "/usr/lib/python3.6/contextlib.py" in inner
  52.                 return func(*args, **kwds)

File "/usr/local/lib/python3.6/dist-packages/django/views/decorators/csrf.py" in wrapped_view
  54.         return view_func(*args, **kwargs)

File "/usr/local/lib/python3.6/dist-packages/rest_framework/viewsets.py" in view
  116.             return self.dispatch(request, *args, **kwargs)

File "/usr/local/lib/python3.6/dist-packages/rest_framework/views.py" in dispatch
  495.             response = self.handle_exception(exc)

File "/usr/local/lib/python3.6/dist-packages/rest_framework/views.py" in handle_exception
  455.             self.raise_uncaught_exception(exc)

File "/usr/local/lib/python3.6/dist-packages/rest_framework/views.py" in dispatch
  492.             response = handler(request, *args, **kwargs)

File "/usr/local/lib/python3.6/dist-packages/rest_framework/mixins.py" in list
  48.         return Response(serializer.data)

File "/usr/local/lib/python3.6/dist-packages/rest_framework/serializers.py" in data
  768.         ret = super(ListSerializer, self).data

File "/usr/local/lib/python3.6/dist-packages/rest_framework/serializers.py" in data
  262.                 self._data = self.to_representation(self.instance)

File "/usr/local/lib/python3.6/dist-packages/rest_framework/serializers.py" in to_representation
  686.             self.child.to_representation(item) for item in iterable

File "/usr/local/lib/python3.6/dist-packages/rest_framework/serializers.py" in <listcomp>
  686.             self.child.to_representation(item) for item in iterable

File "/usr/local/lib/python3.6/dist-packages/rest_framework/serializers.py" in to_representation
  530.                 ret[field.field_name] = field.to_representation(attribute)

File "/usr/local/lib/python3.6/dist-packages/rest_framework/relations.py" in to_representation
  272.         return value.pk

Exception Type: AttributeError at /dqf_api/test_suites/
Exception Value: 'str' object has no attribute 'pk'

router = routers.DefaultRouter()
router.register(r'teams', views.TeamViewSet)
router.register(r'test_suites', views.TestSuiteViewSet)
urlpatterns = [ url(r'^dqf_api/', include(router.urls))]