Addressed comments

Author: rads-1996

opentelemetry-api/src/opentelemetry/attributes/__init__.py

@@ -180,7 +180,14 @@ def _clean_extended_attribute_value(
         # Freeze mutable sequences defensively
         return tuple(cleaned_seq)
 
-    return value
+    try:
+        return str(value)
+    except Exception:
+        raise TypeError(
+            f"Invalid type {type(value).__name__} for attribute value. "
+            f"Expected one of {[valid_type.__name__ for valid_type in _VALID_ANY_VALUE_TYPES]} or a "
+            "sequence of those types",
+        )
 
 
 def _clean_extended_attribute(

opentelemetry-api/tests/attributes/test_attributes.py

@@ -319,16 +319,5 @@ def __str__(self):
         ) as clean_extended_attribute_mock:
             bdict["request"] = wsgi_request
 
-        # Verify that _clean_extended_attribute was called
-        clean_extended_attribute_mock.assert_called_once()
-
-        # Verify that the value passed to _clean_extended_attribute is a string, not the original object
-        call_args = clean_extended_attribute_mock.call_args
-        passed_value = call_args[0][1]  # Second argument is the value
-        self.assertIsInstance(passed_value, str)
-        self.assertNotEqual(
-            passed_value, original_request
-        )  # Should be stringified, not the original object
-        self.assertIn(
-            "DummyWSGIRequest", passed_value
-        )  # String representation includes class name
+        # Verify that the request stored in the bounded dict matches the cleaned value
+        self.assertEqual(bdict["request"], "stringified_request")