Integration with Formstack

Hello,

i am trying to generate a JSON formatted output to send to Formstak to perform a loop to insert a field conatined in a list of dictionaries. The format that works in Formstack (through the testing tab) is the following:

I tried to produce this output with a Zapier Code step, with the following code:

The ouput looks like the same format as I need it 

[ { "Id_num": "01HRWW2N752F8EV5ZZ2TZE0FEF", "Object": "1.2 Paragraph", "Content": "1.2 Paragraph\n\nCum explicabo voluptate At velit consequatur eos corporis consequatur in deleniti illo ut iste aliquid ut consequatur placeat sed esse voluptas. Sed expedita soluta in nihil nesciunt aut error dolorem in tempore ipsam sed adipisci quibusdam et fuga laudantium. Qui optio natus et fugiat impedit sit voluptas repellendus.\n\nQuo velit similique sed accusamus quos vel voluptatem perspiciatis ea obcaecati nobis 33 pariatur soluta. Sit veniam dolore qui consectetur consequatur 33 magnam perferendis qui eligendi reprehenderit ut molestiae provident ab neque galisum. Et necessitatibus praesentium non veniam itaque aut omnis enim.", "Type": "Par" }, { "Id_num": "01HRWVYY5YAJKCB7HG75HH6RDP", "Object": "1.1 Paragraph", "Content": "1.1 Paragraph\n\nLorem ipsum dolor sit amet. Et deserunt quidem et commodi molestias est totam odio ea vitae voluptatem eos unde impedit. 33 architecto quaerat aut architecto ducimus sit consequatur delectus ut cupiditate iste non officiis earum vel necessitatibus doloremque. Non molestiae dolores id culpa vitae et blanditiis repudiandae vel quos dolor in omnis tempora aut labore expedita ut pariatur reiciendis. Vel reprehenderit fugiat et quia dolor sit tempore rerum est aperiam placeat est dolores dolores qui magnam optio et suscipit quia.", "Type": "Par" }, { "Id_num": "01HRWVWY6P3592KTXDKVJHQF7H", "Object": "List of Chapters", "Content": "1. Chapter 1\n2. Chapter 2", "Type": "Chp" }, { "Id_num": "01HRWVWMWN2AFWMVH93FEKBARW", "Object": "Table of Content", "Content": "Table of Content\n\n1. Chapter 1\n 1.1 Paragraph\n 1.2 Paragraph\n\n2. Chapter 2", "Type": "ToC" } ]

But when I run the Formstack step Create Document Merge in Formstack Documents i get the error:

any suggestions? it seems that the format is wrong but the code output should be a JSON object already.

The same output copied and pasted in the formstack webapp test, works!

Thank you!