Update word_frequency_functions.py

Author: cclauss

machine_learning/word_frequency_functions.py

@@ -79,9 +79,9 @@ def document_frequency(term: str, corpus: str) -> int:
         str.maketrans("", "", string.punctuation)
     )  # strip all punctuation and replace it with ''
     documents = corpus_without_punctuation.split("\n")
-    lowercase_documents = [document.lower() for document in documents]
+    lowercase_docs = [document.lower() for document in documents]
     return (
-        len([doc for doc in lowercase_documents if term.lower() in doc]),
+        len([doc for doc in lowercase_docs if term.lower() in doc]),
         len(documents),
     )