diff --git a/src/pychangelogfactory/changelogfactory.py b/src/pychangelogfactory/changelogfactory.py
index ad90e70..b487e0c 100644
--- a/src/pychangelogfactory/changelogfactory.py
+++ b/src/pychangelogfactory/changelogfactory.py
@@ -42,31 +42,31 @@ def _ChangelogFormaterRecordType(Klass: type) -> type:
 
 
 class ChangeLogFormater(ABC):
+    """ChangeLogFormater class
 
-    prefix: str = "^\s+"
-    title: str = "Others :"
-    keywords: list[str] = []
+    This class is the base formater class.
+
+    This class is for:
+
+    - classifying message: CheckLine() and CheckLine_keywords()
+    - storing lines: Clear() and PushLine()
+    - returning the formated output: Render() and RenderLines()
+
+
+    /// warning
+    this class does not aim to be instantiated by user.
+    ///
+    """
+
+    prefix: None | str = None
+    title: None | str = None
+    keywords: None | list[str] = None
     priority: int = 0
 
     _lines: list[str] = []
 
     def __init__(self):
-        """ChangeLogFormater class constructor
-
-        This class is the base formater class.
-
-        This class is for:
-
-        - classifying message: CheckLine() and CheckLine_keywords()
-        - storing lines: Clear() and PushLine()
-        - returning the formated output: Render() and RenderLines()
-
-
-        /// warning
-        this class does not aim to be instantiated by user.
-        ///
-
-        """
+        """ChangeLogFormater class constructor"""
         self._lines = []
 
     def Clear(self) -> None:
@@ -174,12 +174,11 @@ class ChangeLogFactory:
         """
         if self is not None:
             self.ar_FormaterKlass = _savedFormaterList.copy()
-            self.ar_Formater = dict()
+            self.ar_Formater = {}
             for FormaterKlass in self.ar_FormaterKlass:
                 self.ar_Formater[FormaterKlass.__name__] = FormaterKlass()
-            return self
-        else:
-            ChangeLogFactory.ar_FormaterKlass = _savedFormaterList.copy()
+        ChangeLogFactory.ar_FormaterKlass = _savedFormaterList.copy()
+        return None
 
     def RegisterFormater(self, FormaterKlass: ChangeLogFormater) -> None:
         """Register a new formater in the current instance
@@ -276,7 +275,7 @@ class ChangeLogFactory:
             if (lineWordsCount > 1) and (not re.match(self.checkCommentPattern, line)):
                 if self._ProcessLineMain(line) is True:
                     continue
-                elif lineWordsCount > 2:
+                if lineWordsCount > 2:
                     Lines2ndRound.append(line)
 
         for line in Lines2ndRound:
@@ -330,8 +329,8 @@ for RecordType, Config in {
                 ),
     "wip":      (   0,  ["temp", ],
                     "Work in progress changes :construction: :",
-                ), 
-    "doc":     (   0,  [ "doc", "manual"], 
+                ),
+    "doc":     (   0,  [ "doc", "manual"],
                     "Documentations :book: :",
                 ),
     "style":    (   5,  ["beautify", ],
@@ -340,13 +339,13 @@ for RecordType, Config in {
     "refactor": (   0,  [],
                     "Refactorings :recycle: :"
                 ),
-    "ci":       (   0,  ["jenkins", "git"], 
+    "ci":       (   0,  ["jenkins", "git"],
                     "Continuous Integration :cyclone: :"
                 ),
-    "test":     (   -5, ["unittest", "check", "testing"], 
+    "test":     (   -5, ["unittest", "check", "testing"],
                     "Testings :vertical_traffic_light: :"
                 ),
-    "build":    (   0,  ["compile", "version"], 
+    "build":    (   0,  ["compile", "version"],
                     "Builds :package: :"
                 ),
     # fmt: on
diff --git a/test/test_changelogfactory.py b/test/test_changelogfactory.py
index 75db754..bf66011 100644
--- a/test/test_changelogfactory.py
+++ b/test/test_changelogfactory.py
@@ -15,10 +15,10 @@ class Testtest_module(unittest.TestCase):
     def setUp(self):
         ChangeLogFactory.ResetFormaterList()
 
-    def simplegeneration(self, inputstr, teststrs: list[str]):
+    def simplegeneration(self, inputstr, teststrs: list[str], withunknown: bool = False):
         hdlr = ChangeLogFactory()
         hdlr.ProcessFullChangelog(inputstr)
-        changelog = hdlr.RenderFullChangelog()
+        changelog = hdlr.RenderFullChangelog(include_unknown=withunknown)
         for test in teststrs:
             self.assertIn(test, changelog)
 
@@ -52,6 +52,15 @@ class Testtest_module(unittest.TestCase):
         self.assertIn("testdoc", changelog[5])
         self.assertIn("testtest", changelog[7])
 
+    def test_simplegeneration_toosmall(self):
+        self.simplegeneration("one", [], True)
+        self.simplegeneration("one two", [], True)
+        self.simplegeneration("one two three", ["one two three"], True)
+
+    def test_simplegeneration_unknown(self):
+        self.simplegeneration("one two three", ["one two three"], True)
+        self.simplegeneration("one two three", [""], False)
+
     def test_simplegeneration_multiple(self):
         raw = "break: testbreak" + "\n" + "doc: testdoc" + "\n" + "style: teststyle"
         self.simplegeneration(raw, ["testbreak", "testdoc", "teststyle"])