Add tests, use more appropriate fallback type

griptape/schemas/base_schema.py

@@ -107,8 +107,9 @@ def _resolve_types(cls, attrs_cls: type) -> None:
         from griptape.structures import Structure
         from griptape.utils import PromptStack
         from griptape.tokenizers.base_tokenizer import BaseTokenizer
+        from typing import Any
 
-        boto3 = import_optional_dependency("boto3") if is_dependency_installed("boto3") else {}
+        boto3 = import_optional_dependency("boto3") if is_dependency_installed("boto3") else Any
 
         attrs.resolve_types(
             attrs_cls,

tests/unit/utils/test_import_utils.py

@@ -0,0 +1,17 @@
+import pytest
+from griptape.utils import import_optional_dependency, is_dependency_installed
+
+
+class TestImportUtils:
+    def test_import_optional_dependency(self):
+        assert import_optional_dependency("os")
+        assert import_optional_dependency("boto3")
+
+        with pytest.raises(ImportError):
+            assert import_optional_dependency("foobar")
+
+    def test_is_dependency_installed(self):
+        assert is_dependency_installed("os") is True
+        assert is_dependency_installed("boto3") is True
+
+        assert is_dependency_installed("foobar") is False