apply lint to pdl_interpreter.py

Signed-off-by: hirokuni-kitahara <[email protected]>

Author: hirokuni-kitahara

src/pdl/pdl_interpreter.py

@@ -792,14 +792,19 @@ def process_block_body(
                         retry_count += 1
                         error = f"Retry on error is triggered in a repeat block. Error detail: {repr(exc)} "
                         print(f"\n\033[0;31m{error}\033[0m\n")
-                        if (
-                            background
-                            and background.data
-                            and background.data[-1]["content"].endswith(error)
-                        ):
+                        repeating_same_error = False
+                        if background and background.data:
+                            bg_data = background.data
+                            if isinstance(bg_data, list):
+                                last_error = bg_data[-1]["content"]
+                                if isinstance(last_error, str):
+                                    if last_error.endswith(error):
+                                        repeating_same_error = True
+                        if repeating_same_error:
                             error = "The previous error occurs multiple times."
                         background = lazy_messages_concat(
-                            background, [{"role": "assistant", "content": error}]
+                            background,
+                            PdlList([{"role": "assistant", "content": error}]),
                         )
                     else:
                         raise PDLRuntimeError(