Freeze defaultdict

src/dictionaries/morphosyntactic/ner_file.py

@@ -57,6 +57,9 @@ class NERFileMorphosyntacticDictionary(MorphosyntacticDictionary):
                 ner_tag, word, lemma, morpho_tag = line.split("\t")
                 replacement_dictionary[ner_tag][morpho_tag][lemma] = word
 
+        replacement_dictionary = {k: dict(v) for k, v
+                                  in replacement_dictionary.items()
+                                  if v}  # freeze dict
         return replacement_dictionary
 
     def get_supported_detection_classes(self) -> List[Type[Detection]]: