* add flake 8 check
* split up litellm _acompletion
* fix get model client
* refactor use commong func to add metadata to kwargs
* use common func to get timeout
* re-use helper to _get_async_model_client
* use _handle_mock_testing_rate_limit_error
* fix docstring for _handle_mock_testing_rate_limit_error
* fix function_with_retries
* use helper for mock testing fallbacks
* router - use 1 func for simple_shuffle
* add doc string for simple_shuffle
* use 1 function for filtering cooldown deployments
* fix use common helper to _get_fallback_model_group_from_fallbacks
* track api key and team in prom latency metric
* add test for latency metric
* test prometheus success metrics for latency
* track team and key labels for deployment failures
* add test for litellm_deployment_failure_responses_total
* fix checks for premium user on prometheus
* log_success_fallback_event and log_failure_fallback_event
* log original_exception in log_success_fallback_event
* track key, team and exception status and class on fallback metrics
* use get_standard_logging_metadata
* fix import error
* track litellm_deployment_successful_fallbacks
* add test test_proxy_fallback_metrics
* add log log_success_fallback_event
* fix test prometheus
