'Basic test of the partition_group_info accessor function'

def test_get_group_info_for_cohort(self):

    self.assertEqual(cohorts.get_group_info_for_cohort(self.first_cohort), (None, None))
    link = self._link_cohort_partition_group(self.first_cohort, self.partition_id, self.group1_id)
    self.assertEqual(cohorts.get_group_info_for_cohort(self.first_cohort), (self.group1_id, self.partition_id))
    link.delete()
    self.assertEqual(cohorts.get_group_info_for_cohort(self.first_cohort), (None, None))
