468     since handling operations becomes coslty on massive data import.

   468     since handling operations becomes coslty on massive data import.

   469     """

   469     """

   470     try:

   470     try:

   471         session.transaction_data[datakey].add(value)

   471         session.transaction_data[datakey].add(value)

   472     except KeyError:

   472     except KeyError:

   474         session.transaction_data[datakey] = set((value,))

   474         session.transaction_data[datakey] = set((value,))

   475 

   475 

   476 

   476 

   477 class LateOperation(Operation):

   477 class LateOperation(Operation):

   478     """special operation which should be called after all possible (ie non late)

   478     """special operation which should be called after all possible (ie non late)