diff --git a/atom_evaluation/scripts/other_calibrations/rwhe_calib_ali.py b/atom_evaluation/scripts/other_calibrations/rwhe_calib_ali.py
index bd1478f1..e649f139 100755
--- a/atom_evaluation/scripts/other_calibrations/rwhe_calib_ali.py
+++ b/atom_evaluation/scripts/other_calibrations/rwhe_calib_ali.py
@@ -1,7 +1,8 @@
 #!/usr/bin/env python3
 
 import argparse
-import json
+
+from atom_core.dataset_io import loadResultsJSON
 
 def main():
     
@@ -9,18 +10,21 @@ def main():
     ap = argparse.ArgumentParser()
     ap.add_argument("-json", "--json_file", type=str, required=True,
                     help="Json file containing input dataset.")
+    ap.add_argument("-csf", "--collection_selection_function", default=None, type=str,
+                    help="A string to be evaluated into a lambda function that receives a collection name as input and "
+                    "returns True or False to indicate if the collection should be loaded (and used in the "
+                    "optimization). The Syntax is lambda name: f(x), where f(x) is the function in python "
+                    "language. Example: lambda name: int(name) > 5 , to load only collections 6, 7, and onward.")
+    
     args = vars(ap.parse_args())
 
     json_file = args['json_file']
+    collection_selection_function = args['collection_selection_function']
 
     # Read dataset file
-    f = open(json_file, 'r')
-    dataset = json.load(f)
+    dataset, json_file = loadResultsJSON(json_file, collection_selection_function)
 
-    # Close dataset file
-    f.close()
-
-    print(dataset)  
+    
 
 
 if __name__ == '__main__':