more sturdy function to work with annotations

Author: giograno

src/py_avro_schema/_schemas.py

@@ -26,6 +26,7 @@
 import re
 import sys
 import types
+import typing
 import uuid
 from enum import StrEnum
 from typing import (
@@ -1280,7 +1281,7 @@ def handles_type(cls, py_type: Type) -> bool:
             # If we are subclassing a string, used the "named string" approach
             and (inspect.isclass(py_type) and not issubclass(py_type, str))
             # and any other class with typed annotations
-            and bool(get_type_hints(py_type))
+            and has_annotations(py_type)
         )
 
     def __init__(
@@ -1453,3 +1454,13 @@ def _type_from_annotated(py_type: Type) -> Type:
         return args[0]
     else:
         return py_type
+
+
+def has_annotations(py_type: Type) -> bool:
+    """Checks if a type has annotations"""
+    py_type = _type_from_annotated(py_type)
+    try:
+        return bool(typing.get_type_hints(py_type))
+    except Exception:
+        pass
+    return hasattr(py_type, "__annotations__")