Refactor, breaking code into modules.

dictionary.py

@@ -1,5 +1,7 @@
 #!/usr/bin/python
 
+import h5py
+
 WORDLE_LENGTH = 5
 
 
@@ -63,17 +65,26 @@ _invalid_words = set(
 )
 
 
-_wordle_dictionary = set()
+class WordleWords:
+    _words = set()
+
+    def __init__(self, filename):
+        if not self._words:
+            with open("words_alpha.txt") as word_file:
+                all_words = word_file.read().split()
+            self._words.update(
+                filter(
+                    lambda w: len(w) == WORDLE_LENGTH and w not in _invalid_words,
+                    all_words,
+                )
+            )
+
+    def _initialize_db(self):
+        pass
+
+    def __iter__(self):
+        return iter(self._words)
 
 
 def words():
-    if not _wordle_dictionary:
-        with open("words_alpha.txt") as word_file:
-            all_words = word_file.read().split()
-        _wordle_dictionary.update(
-            filter(
-                lambda w: len(w) == WORDLE_LENGTH and w not in _invalid_words, all_words
-            )
-        )
-
-    return _wordle_dictionary
+    return WordleWords(filename="dictionary.hdf5")