fix: FunctionBlock function attribute should have default None

Pin  openai=1.61.0 BerriAI/litellm#9424

Signed-off-by: Nick Mitchell <[email protected]>

Author: starpit

pyproject.toml

@@ -13,6 +13,7 @@ dependencies = [
   "PyYAML~=6.0",
   "jsonschema~=4.0",
   "litellm>=1.57.3,!=1.59.9,!=1.63.14",
+  "openai==1.61.0",
   "termcolor~=2.0",
   "ipython>=8,<10",
   "json-repair~=0.35",

src/pdl/pdl_ast.py

@@ -273,7 +273,7 @@ class FunctionBlock(LeafBlock):
     """Function declaration."""
 
     kind: Literal[BlockKind.FUNCTION] = BlockKind.FUNCTION
-    function: Optional[dict[str, Any]]
+    function: Optional[dict[str, Any]] = None
     """Functions parameters with their types.
     """
     returns: "BlockType" = Field(..., alias="return")