Changed
- The `check in` feature now sends two additional action arguments,
`_changed` and `_initial`. These arguments are not reported by
`action_arguments()` but can be retrieved with `action_argument()`.
- The `defined()`, `value()`, and `showifdef()` functions now accept a
keyword argument `prior` which can be set to `True` in order to
correctly handle situations where the user has just clicked the Back
button and it is necessary to know the value that a variable had
prior to the user pressing the Back button. If `prior` is `True`,
the set of interview answers that was just discarded will be
accessed first, and then the current interview answers will be
accessed. In situations where the user has not just pressed the Back
button, setting `prior` to `True` has no effect.
- The `countries_list()` and `states_list()` functions now return
alphabetically sorted results. `states_list()` returns an empty
dictionary when the `country_code` is invalid.
- When the second argument of `background_response()` is `'fields'`,
and the first argument is a dictionary of variable names and values,
the value of a dropdown field can be set to a dictionary with keys
`value` and `choices`. The `choices` will replace the options in the
dropdown for that field.
Fixed
- Upgraded `pikepdf` and fixed issue with way it is called.