fix: adjust exception message structure

graphene/types/tests/test_uuid.py

@@ -47,7 +47,7 @@ def test_uuidstring_invalid_argument():
     assert len(result.errors) == 1
     assert (
         result.errors[0].message
-        == "Variable '$uuid' got invalid value {'not': 'a string'}; UUID must be a string"
+        == "Variable '$uuid' got invalid value {'not': 'a string'}; UUID cannot represent value: {'not': 'a string'}"
     )
 
 

graphene/types/uuid.py

@@ -29,6 +29,9 @@ class UUID(Scalar):
 
     @staticmethod
     def parse_value(value):
-        if not isinstance(value, (str, _UUID)):
-            raise GraphQLError("UUID must be a string")
-        return _UUID(value)
+        if isinstance(value, _UUID):
+            return value
+        try:
+            return _UUID(value)
+        except (ValueError, AttributeError):
+            raise GraphQLError(f"UUID cannot represent value: {repr(value)}")