diff --git a/cvss/cvss2.py b/cvss/cvss2.py
index 6b64df4..cc85b98 100644
--- a/cvss/cvss2.py
+++ b/cvss/cvss2.py
@@ -321,14 +321,6 @@ def rh_vector(self):
         """
         return str(self.scores()[0]) + "/" + self.clean_vector()
 
-    def __eq__(self, o):
-        if isinstance(o, CVSS2):
-            return self.clean_vector().__eq__(o.clean_vector())
-        return NotImplemented
-
-    def __hash__(self):
-        return hash(self.clean_vector())
-
     def as_json(self, sort=False, minimal=False):
         """
         Returns a dictionary formatted with attribute names and values defined by the official
@@ -381,3 +373,11 @@ def add_metric_to_data(metric):
             data = OrderedDict(sorted(data.items()))
 
         return data
+
+    def __hash__(self):
+        return hash(self.clean_vector())
+
+    def __eq__(self, o):
+        if isinstance(o, CVSS2):
+            return self.clean_vector() == o.clean_vector()
+        return False
diff --git a/cvss/cvss3.py b/cvss/cvss3.py
index f80840a..da386ec 100644
--- a/cvss/cvss3.py
+++ b/cvss/cvss3.py
@@ -441,14 +441,6 @@ def rh_vector(self):
         """
         return str(self.scores()[0]) + "/" + self.clean_vector()
 
-    def __eq__(self, o):
-        if isinstance(o, CVSS3):
-            return self.clean_vector().__eq__(o.clean_vector())
-        return NotImplemented
-
-    def __hash__(self):
-        return hash(self.clean_vector())
-
     def as_json(self, sort=False, minimal=False):
         """
         Returns a dictionary formatted with attribute names and values defined by the official
@@ -508,3 +500,11 @@ def add_metric_to_data(metric):
         if sort:
             data = OrderedDict(sorted(data.items()))
         return data
+
+    def __hash__(self):
+        return hash(self.clean_vector())
+
+    def __eq__(self, o):
+        if isinstance(o, CVSS3):
+            return self.clean_vector() == o.clean_vector()
+        return False
diff --git a/cvss/cvss4.py b/cvss/cvss4.py
index 63873a8..2945eb8 100644
--- a/cvss/cvss4.py
+++ b/cvss/cvss4.py
@@ -549,9 +549,6 @@ def compute_base_score(self):
 
         self.base_score = round_away_from_zero(value)
 
-    def __hash__(self):
-        return hash(self.clean_vector())
-
     def clean_vector(self, output_prefix=True):
         """
         Returns vector without optional metrics marked as X and in preferred order.
@@ -670,3 +667,11 @@ def add_metric_to_data(metric):
         if sort:
             data = OrderedDict(sorted(data.items()))
         return data
+
+    def __hash__(self):
+        return hash(self.clean_vector())
+
+    def __eq__(self, o):
+        if isinstance(o, CVSS4):
+            return self.clean_vector() == o.clean_vector()
+        return False