code: def serialize(self, cls, record):
          
          return json.dumps(record, cls=self.encoder)
docs: Serialize the record to JSON. cls unused in this implementation.
  
          >>> s = teststore()
          >>> s.serialize('tstoretest', {'id': '1', 'name': 'Toto'})
          '{"id": "1", "name": "Toto"}'