diff --git a/main.py b/main.py
index f2e80a5..a9ac083 100644
--- a/main.py
+++ b/main.py
@@ -89,9 +89,9 @@ async def fastapi_export_inp(network: str) -> ChangeSet:
     cs = export_inp(network)
     op = cs.operations[0]
     open_project(network)
-    op['vertex'] = str(get_all_vertices(network))
+    op['vertex'] = json.dumps(get_all_vertices(network))
     print(op['vertex'])
-    op['scada'] = str(get_all_scada_elements(network))
+    op['scada'] = json.dumps(get_all_scada_elements(network))
     close_project(network)
 
     return cs