Professional Way
{"is-c3-clipboard-data":true,"type":"events","items":[{"eventType":"block","conditions":[{"id":"on-start-of-layout","objectClass":"System"}],"actions":[{"id":"request-project-file","objectClass":"AJAX","parameters":{"tag":"\"file\"","file":"file.json"}}]},{"eventType":"block","conditions":[{"id":"on-completed","objectClass":"AJAX","parameters":{"tag":"\"file\""}}],"actions":[{"id":"parse","objectClass":"JSON","parameters":{"data":"AJAX.LastData"}}]}]}
Simpler way
{"is-c3-clipboard-data":true,"type":"events","items":[{"eventType":"block","conditions":[{"id":"on-start-of-layout","objectClass":"System"}],"actions":[{"id":"request-project-file","objectClass":"AJAX","parameters":{"tag":"\"file\"","file":"file.json"}},{"id":"wait-for-previous-actions","objectClass":"System"},{"id":"parse","objectClass":"JSON","parameters":{"data":"AJAX.LastData"}}]}]}