Sourceval to_value :
AppBlock.t list->[> `List of
[> `Structure of
(string
* [> `Enum of string| `List of
[> `Structure of (string * [> `String of String_.t ]) list ]
list| `String of String_.t| `Structure of
(string
* [> `Integer of Integer.t| `String of S3Bucket.t| `Structure of (string * [> `String of S3Bucket.t ]) list ])
list| `Timestamp of Timestamp.t ])
list ]
list ]