code: def existingInStore(cls, store, storeID, attrs):
          
          self = cls.__new__(cls)
  
          self.__justCreated = False
          self.__subinit__(__store=store,
                           storeID=storeID,
                           __everInserted=True)
  
          schema = self.getSchema()
          assert len(schema) == len(attrs), "invalid number of attributes"
          for data, (name, attr) in zip(attrs, schema):
              attr.loaded(self, data)
          self.activate()
          return self
docs: Create and return a new instance from a row from the store.