new_contents: from database import db
  from model_testing import ModelTest
  from models import Cancer
  from sqlalchemy.exc import IntegrityError
  import pytest
  
  
  class CancerTest(ModelTest):
  
      def test_init(self):
  
          cancer = Cancer(name='Bladder Urothelial Carcinoma',  code='BLCA')
  
          assert cancer.name == 'Bladder Urothelial Carcinoma'
          assert cancer.code == 'BLCA'
  
          db.session.add(cancer)
  
          the_same_code = Cancer(name='Colon adenocarcinoma',  code='BLCA')
          the_same_name = Cancer(name='Bladder Urothelial Carcinoma',  code='BRCA')
  
          with pytest.raises(IntegrityError):
              db.session.add(the_same_code)
              db.session.commit()
  
          # return to previous state, cancer needs to be re-added
          db.session.rollback()
          db.session.add(cancer)
  
          with pytest.raises(IntegrityError):
              db.session.add(the_same_name)
              db.session.commit()
  
subject: Add tests for cancer model init