OptionalcalculateOptionalexecuteExecutes a custom host operation.
The payload is required to have a type attribute used to distinguish between different operations.
If the host encounters an operation it is not equipped to handle,
it should throw an error with the name set to NotSupportedError.
OptionalrestoreRestores a planning from a backend.
The backend should return the data that was saved with the pin.
Will only be used when save is also implemented.
OptionalsaveSaves plannings to a backend.
The backend should return a pin that can be used to restore the planning.
Will only be used when restore is also implemented.
Calculates prices.