diff --git a/litellm/llms/infinity/common_utils.py b/litellm/llms/infinity/common_utils.py
index e23fe4a0d37..30a5f1006f7 100644
--- a/litellm/llms/infinity/common_utils.py
+++ b/litellm/llms/infinity/common_utils.py
@@ -4,7 +4,8 @@ from litellm.llms.base_llm.chat.transformation import BaseLLMException
 
 
 class InfinityError(BaseLLMException):
-    def __init__(self, status_code: int, message: str, headers: dict | httpx.Headers = {}):
+    def __init__(self, status_code: int, message: str, headers: dict | httpx.Headers | None = None):
+        resolved_headers = {} if headers is None else headers
         self.status_code = status_code
         self.message = message
         self.request = httpx.Request(method="POST", url="https://github.com/michaelfeil/infinity")
@@ -14,5 +15,5 @@ class InfinityError(BaseLLMException):
             message=message,
             request=self.request,
             response=self.response,
-            headers=headers,
+            headers=resolved_headers,
         )  # Call the base class constructor with the parameters it needs
diff --git a/litellm/llms/vertex_ai/gemini/transformation.py b/litellm/llms/vertex_ai/gemini/transformation.py
index e3cc3bbb2dc..80b35a03f95 100644
--- a/litellm/llms/vertex_ai/gemini/transformation.py
+++ b/litellm/llms/vertex_ai/gemini/transformation.py
@@ -616,12 +616,15 @@ def _get_equivalent_key(key: str, available_keys: set) -> str | None:
     return None
 
 
-def check_if_part_exists_in_parts(parts: list[PartType], part: PartType, excluded_keys: list[str] = []) -> bool:
+def check_if_part_exists_in_parts(
+    parts: list[PartType], part: PartType, excluded_keys: list[str] | None = None
+) -> bool:
     """
     Check if a part exists in a list of parts
     Handles both camelCase and snake_case key variations (e.g., function_call vs functionCall)
     """
-    keys_to_compare: Final = set(part.keys()) - set(excluded_keys)
+    resolved_excluded_keys = [] if excluded_keys is None else excluded_keys
+    keys_to_compare: Final = set(part.keys()) - set(resolved_excluded_keys)
     for p in parts:
         p_keys = set(p.keys())
         # Check if all keys in part have equivalent values in p