Values.SynthesisTasksSourceval to_value :
SynthesisTask.t list ->
[> `List of
[> `Structure of
(string
* [> `Enum of string
| `Integer of RequestCharacters.t
| `List of [> `Enum of string | `String of LexiconName.t ] list
| `String of TaskId.t
| `Timestamp of DateTime.t ])
list ]
list ]