diff --git a/apiserver/main.py b/apiserver/main.py
index bf55e3f034167ad68a93d7f33ec6fb6ce1ef9371..2bb64cc013d81ce1f7a86f61cfe195a96b216ba5 100644
--- a/apiserver/main.py
+++ b/apiserver/main.py
@@ -4,7 +4,7 @@ Main module of data catalog api
 import logging
 from datetime import timedelta
 from enum import Enum
-from typing import Dict, List, Tuple
+from typing import List, Tuple
 
 from fastapi import FastAPI, HTTPException, Request, status
 from fastapi.param_functions import Depends
@@ -84,7 +84,7 @@ async def get_specific_dataset(location_data_type: LocationDataType, dataset_id:
     """returns all information about a specific dataset, identified by id"""
     return adapter.get_details(location_data_type, dataset_id)
 
-@app.post("/{location_data_type}", response_model=Dict[str, LocationData])
+@app.post("/{location_data_type}", response_model=Tuple[str, LocationData])
 async def add_dataset(location_data_type: LocationDataType,
                       dataset: LocationData,
                       user: User = Depends(my_user)):
@@ -92,7 +92,7 @@ async def add_dataset(location_data_type: LocationDataType,
     return adapter.add_new(location_data_type, dataset, user.username)
 
 
-@app.put("/{location_data_type}/{dataset_id}", response_model=Dict[str, LocationData])
+@app.put("/{location_data_type}/{dataset_id}", response_model=Tuple[str, LocationData])
 async def update_specific_dataset(location_data_type: LocationDataType,
                                   dataset_id: str, dataset: LocationData,
                                   user: User = Depends(my_user)):
diff --git a/apiserver/storage/JsonFileStorageAdapter.py b/apiserver/storage/JsonFileStorageAdapter.py
index 8dd438b244e733792b6a2b5fefae3d3105b160c2..bdae20d03f860377e0d0a8df05d7edaa255b4318 100644
--- a/apiserver/storage/JsonFileStorageAdapter.py
+++ b/apiserver/storage/JsonFileStorageAdapter.py
@@ -73,7 +73,7 @@ class JsonFileStorageAdapter(AbstractLocationDataStorageAdapter):
         to_store = StoredData(users=[user_name], actualData=data)
         with open(os.path.join(localpath, oid), 'w') as json_file:
             json.dump(to_store.dict(), json_file)
-        return {oid : data}
+        return (oid, data)
 
     def get_details(self, n_type: LocationDataType, oid: str):
         full_path = self.__get_object_path(value=n_type.value, oid=oid)
@@ -89,7 +89,7 @@ class JsonFileStorageAdapter(AbstractLocationDataStorageAdapter):
         with open(full_path, 'w') as f:
             json.dump(obj.dict(), f)
 
-        return {oid : data}
+        return (oid, data)
 
     def delete(self, n_type: LocationDataType, oid: str, usr: str):
         full_path = self.__get_object_path(value=n_type.value, oid=oid)