diff --git a/rest_framework/exceptions.py b/rest_framework/exceptions.py
index 345a40524..8c9d8f8ec 100644
--- a/rest_framework/exceptions.py
+++ b/rest_framework/exceptions.py
@@ -74,7 +74,10 @@ class ErrorDetail(str):
     def __eq__(self, other):
         r = super().__eq__(other)
         try:
-            return r and self.code == other.code
+            if r is not NotImplemented:
+                return r and self.code == other.code
+            else:
+                return self.code == other.code
         except AttributeError:
             return r