diff --git a/barrOs_library.py b/barrOs_library.py
index 1cf84233171571aca4cba66d09fbc0df90324ca6..a143c35d6eb8d17073e00993e0ae267ef8743ab9 100644
--- a/barrOs_library.py
+++ b/barrOs_library.py
@@ -2532,7 +2532,7 @@ def run_barros(arguments, offset = 1, step = 2, local_angle_threshold = 25, max_
                                 save_hairpins(pdb_sequence, pdb_file, barrel_topology, chains=chains, outfolder='hairpins')
 
                             # save intermediate collected data
-                            json.dump(data, outdata, indent=4)
+                            json.dump(data, open(outdata, 'w'), indent=4)
 
 
                         else: