[Refactor] litellm/init.py: lazy-load AmazonConverseConfig (#18069)

- Add LLM_CONFIG_NAMES tuple and _lazy_import_llm_configs function in _lazy_imports.py
- Remove direct import of AmazonConverseConfig from __init__.py
- Add lazy loading handler in __getattr__ to dispatch LLM config imports
- Add type stub for AmazonConverseConfig in TYPE_CHECKING block
- Add test_llm_config_lazy_imports test to verify lazy loading works
- Follows same pattern as DOTPROMPT_NAMES for consistency

litellm/__init__.py

@@ -1055,7 +1055,6 @@ from .utils import client
 
 from .llms.bytez.chat.transformation import BytezChatConfig
 from .llms.custom_llm import CustomLLM
-from .llms.bedrock.chat.converse_transformation import AmazonConverseConfig
 from .llms.openai_like.chat.handler import OpenAILikeChatConfig
 from .llms.aiohttp_openai.chat.transformation import AiohttpOpenAIChatConfig
 from .llms.galadriel.chat.transformation import GaladrielChatConfig
@@ -1551,6 +1550,9 @@ if TYPE_CHECKING:
     module_level_aclient: AsyncHTTPHandler
     module_level_client: HTTPHandler
 
+    # LLM config classes - lazy loaded only
+    AmazonConverseConfig: Type[Any]
+
 
 def __getattr__(name: str) -> Any:
     """Lazy import handler"""
@@ -1565,6 +1567,7 @@ def __getattr__(name: str) -> Any:
         CACHING_NAMES,
         HTTP_HANDLER_NAMES,
         DOTPROMPT_NAMES,
+        LLM_CONFIG_NAMES,
     )
     
     # Lazy load cost_calculator functions
@@ -1619,6 +1622,12 @@ def __getattr__(name: str) -> Any:
 
         return _lazy_import_dotprompt(name)
 
+    # Lazy load LLM config classes
+    if name in LLM_CONFIG_NAMES:
+        from ._lazy_imports import _lazy_import_llm_configs
+
+        return _lazy_import_llm_configs(name)
+
     raise AttributeError(f"module {__name__!r} has no attribute {name!r}")
 
 

litellm/_lazy_imports.py

@@ -154,6 +154,11 @@ DOTPROMPT_NAMES = (
     "set_global_prompt_directory",
 )
 
+# LLM config classes that support lazy loading via _lazy_import_llm_configs
+LLM_CONFIG_NAMES = (
+    "AmazonConverseConfig",
+)
+
 # Lazy import for utils module - imports only the requested item by name.
 # Note: PLR0915 (too many statements) is suppressed because the many if statements
 # are intentional - each attribute is imported individually only when requested,
@@ -611,4 +616,19 @@ def _lazy_import_dotprompt(name: str) -> Any:
         _globals["set_global_prompt_directory"] = _set_global_prompt_directory
         return _set_global_prompt_directory
 
-    raise AttributeError(f"Dotprompt lazy import: unknown attribute {name!r}")
+    raise AttributeError(f"Dotprompt lazy import: unknown attribute {name!r}")
+
+
+def _lazy_import_llm_configs(name: str) -> Any:
+    """Lazy import for LLM config classes."""
+    _globals = _get_litellm_globals()
+
+    if name == "AmazonConverseConfig":
+        from .llms.bedrock.chat.converse_transformation import (
+            AmazonConverseConfig as _AmazonConverseConfig,
+        )
+
+        _globals["AmazonConverseConfig"] = _AmazonConverseConfig
+        return _AmazonConverseConfig
+
+    raise AttributeError(f"LLM config lazy import: unknown attribute {name!r}")

litellm/utils.py

@@ -8393,3 +8393,17 @@ def should_run_mock_completion(
     if mock_response or mock_tool_calls or mock_timeout:
         return True
     return False
+
+
+# Re-export encoding from main.py for backward compatibility
+# This allows tests to import: from litellm.utils import encoding
+# We use a lazy import to avoid loading main.py at utils.py import time
+def __getattr__(name: str) -> Any:
+    """Lazy import handler for utils module"""
+    if name == "encoding":
+        from litellm.main import encoding as _encoding
+        # Cache it in the module's __dict__ for subsequent accesses
+        import sys
+        sys.modules[__name__].__dict__["encoding"] = _encoding
+        return _encoding
+    raise AttributeError(f"module {__name__!r} has no attribute {name!r}")

tests/test_litellm/test_lazy_imports.py

@@ -29,6 +29,8 @@ from litellm._lazy_imports import (
     _lazy_import_http_handlers,
     DOTPROMPT_NAMES,
     _lazy_import_dotprompt,
+    LLM_CONFIG_NAMES,
+    _lazy_import_llm_configs,
 )
 
 
@@ -208,3 +210,20 @@ def test_unknown_attribute_raises_error():
     with pytest.raises(AttributeError):
         _lazy_import_types_utils("unknown")
 
+    with pytest.raises(AttributeError):
+        _lazy_import_llm_configs("unknown")
+
+
+def test_llm_config_lazy_imports():
+    """Test that LLM config classes can be lazy imported."""
+    for name in LLM_CONFIG_NAMES:
+        _clear_names_from_globals(LLM_CONFIG_NAMES)
+
+        obj = _lazy_import_llm_configs(name)
+        assert obj is not None
+        assert name in litellm.__dict__
+        # Config classes should be classes/types
+        assert isinstance(obj, type), f"{name} should be a class"
+
+        _verify_only_requested_name_imported(name, LLM_CONFIG_NAMES)
+