diff --git a/litellm/caching/base_cache.py b/litellm/caching/base_cache.py
index fb91d13a8c9..4dc894a64ba 100644
--- a/litellm/caching/base_cache.py
+++ b/litellm/caching/base_cache.py
@@ -9,14 +9,7 @@ Has 4 methods:
 """
 
 from abc import ABC, abstractmethod
-from typing import TYPE_CHECKING, Any, Final
-
-if TYPE_CHECKING:
-    from opentelemetry.trace import Span as _Span
-
-    Span = _Span
-else:
-    Span = Any
+from typing import Final
 
 
 class BaseCache(ABC):
diff --git a/litellm/integrations/levo/levo.py b/litellm/integrations/levo/levo.py
index 6273f39e09c..c1852e9bfe4 100644
--- a/litellm/integrations/levo/levo.py
+++ b/litellm/integrations/levo/levo.py
@@ -4,8 +4,6 @@ from typing import TYPE_CHECKING, Any, Final
 from litellm.integrations.opentelemetry import OpenTelemetry
 
 if TYPE_CHECKING:
-    from opentelemetry.trace import Span as _Span
-
     from litellm.integrations.opentelemetry import (
         OpenTelemetryConfig as _OpenTelemetryConfig,
     )
@@ -13,11 +11,9 @@ if TYPE_CHECKING:
 
     Protocol = _Protocol
     OpenTelemetryConfig = _OpenTelemetryConfig
-    Span = _Span
 else:
     Protocol = Any
     OpenTelemetryConfig = Any
-    Span = Any
 
 
 class LevoConfig:
diff --git a/litellm/litellm_core_utils/dot_notation_indexing.py b/litellm/litellm_core_utils/dot_notation_indexing.py
index 09720fa413c..818cf1b9695 100644
--- a/litellm/litellm_core_utils/dot_notation_indexing.py
+++ b/litellm/litellm_core_utils/dot_notation_indexing.py
@@ -181,7 +181,7 @@ def _delete_nested_value_custom(
 
 
 def delete_nested_value(
-    data: dict[str, object],
+    data: Mapping[str, object],
     path: str,
     depth: int = 0,
     max_depth: int = 20,
@@ -214,7 +214,7 @@ def delete_nested_value(
     """
     import copy
 
-    result: Final = copy.deepcopy(data)
+    result: Final = copy.deepcopy(data if isinstance(data, dict) else dict(data))
 
     try:
         # Parse path into segments
diff --git a/litellm/proxy/client/models.py b/litellm/proxy/client/models.py
index 7342974c0cc..1361a3e6364 100644
--- a/litellm/proxy/client/models.py
+++ b/litellm/proxy/client/models.py
@@ -168,7 +168,7 @@ class ModelsManagementClient:
             return_request (bool): If True, returns the prepared request object instead of executing it
 
         Returns:
-            Union[Dict[str, Any], requests.Request]: Either the model information from the server or
+            dict[str, object] | requests.Request: Either the model information from the server or
             a prepared request object if return_request is True
 
         Raises:
diff --git a/tests/unit/litellm_core_utils/test_dot_notation_indexing.py b/tests/unit/litellm_core_utils/test_dot_notation_indexing.py
index ae529a71009..7c670f1dac9 100644
--- a/tests/unit/litellm_core_utils/test_dot_notation_indexing.py
+++ b/tests/unit/litellm_core_utils/test_dot_notation_indexing.py
@@ -2,6 +2,9 @@
 Tests for litellm.litellm_core_utils.dot_notation_indexing module.
 """
 
+from types import MappingProxyType
+from typing import Final
+
 import pytest
 
 from litellm.litellm_core_utils.dot_notation_indexing import (
@@ -125,3 +128,14 @@ class TestDeleteNestedValue:
         data = {"items": [{"a": 1, "b": 2}, {"a": 3, "b": 4}]}
         result = delete_nested_value(data, "items[0].b")
         assert result == {"items": [{"a": 1}, {"a": 3, "b": 4}]}
+
+    def test_delete_returns_a_fresh_dict_and_leaves_a_narrowly_typed_input_untouched(self):
+        payload: Final[dict[str, list[str]]] = {"tags": ["a", "b"], "secret": ["s"]}
+        result = delete_nested_value(payload, "secret")
+        assert result == {"tags": ["a", "b"]}
+        assert payload == {"tags": ["a", "b"], "secret": ["s"]}
+        assert result["tags"] is not payload["tags"]
+
+    def test_delete_accepts_a_read_only_mapping(self):
+        payload: Final = MappingProxyType({"tags": ["a"], "secret": ["s"]})
+        assert delete_nested_value(payload, "secret") == {"tags": ["a"]}