- Added `create_function` and `async_create_function` class attributes with default implementations in `base_provider.py` for `AbstractProvider`, `AsyncProvider`, and `AsyncGeneratorProvider`
- Updated `get_create_function` and `get_async_create_function` methods to return these class attributes
- Replaced calls to `provider.get_create_function()` and `provider.get_async_create_function()` with direct attribute access `provider.create_function` and `provider.async_create_function` across `g4f/__init__.py`, `g4f/client/__init__.py`, `g4f/providers/retry_provider.py`, and `g4f/tools/run_tools.py`
- Removed redundant `get_create_function` and `get_async_create_function` methods from `providers/base_provider.py` and `providers/types.py`
- Ensured all provider response calls now use the class attributes for creating completions asynchronously and synchronously as needed