Added singleton to common code

Author: LeonardPuettmannKern

extractors/personal_identifiers/location_extraction/code_snippet_common.md

@@ -2,15 +2,20 @@
 import spacy
 from typing import List, Tuple
 
-nlp = spacy.load("en_core_web_sm")
+loaded_models = {}
+def load_spacy(spacy_model):
+    if spacy_model not in loaded_models:  
+        loaded_models[spacy_model] = spacy.load(spacy_model)
+    return loaded_models[spacy_model]
 
-def location_extraction(text: str, extraction_keyword: str) -> List[Tuple[str, int]]:
+
+def location_extraction(text: str, extraction_keyword: str, spacy_model: str = "en_core_web_sm") -> List[Tuple[str, int]]:
     """
     @param text: the input text
     @param extraction_keyword: the label that is assigned to extracted words
     @return: positions of extracted names of persons  
     """
-
+    nlp = load_spacy(spacy_model)
     doc = nlp(text)
 
     name_positions = []
@@ -19,6 +24,7 @@ def location_extraction(text: str, extraction_keyword: str) -> List[Tuple[str, i
             name_positions.append((extraction_keyword, ent.start, ent.end))
     return name_positions
 
+
 # ↑ necessary bricks function 
 # -----------------------------------------------------------------------------------------
 # ↓ example implementation
@@ -34,4 +40,4 @@ def example_integration():
             print(f"text: \"{text}\" doesn't have {label}")
 
 example_integration()
-```
+```