1 files changed, 9 insertions, 5 deletions
diff --git a/rdflib/exceptions.py b/rdflib/exceptions.py
index 2d71e6e2..708756ef 100644
--- a/rdflib/exceptions.py
+++ b/rdflib/exceptions.py
@@ -5,13 +5,17 @@ TODO:
 __all__ = [
     "Error",
     "ParserError",
+    "UniquenessError",
 ]
 
 
+from typing import Any, Optional
+
+
 class Error(Exception):
     """Base class for rdflib exceptions."""
 
-    def __init__(self, msg=None):
+    def __init__(self, msg: Optional[str] = None):
         Exception.__init__(self, msg)
         self.msg = msg
 
@@ -19,18 +23,18 @@ class Error(Exception):
 class ParserError(Error):
     """RDF Parser error."""
 
-    def __init__(self, msg):
+    def __init__(self, msg: str):
         Error.__init__(self, msg)
-        self.msg = msg
+        self.msg: str = msg
 
-    def __str__(self):
+    def __str__(self) -> str:
         return self.msg
 
 
 class UniquenessError(Error):
     """A uniqueness assumption was made in the context, and that is not true"""
 
-    def __init__(self, values):
+    def __init__(self, values: Any):
         Error.__init__(
             self,
             "\