ONNX Converter and Optimization Tools

The `onnxconverter-common` package provides common functions and utilities for use in converters from various AI frameworks to ONNX. It also enables different converters to work together, such as converting a scikit-learn pipeline embedding an XGBoost model. It is actively maintained by Microsoft with frequent releases, often tied to ONNX and ONNX Runtime updates, focusing on compatibility and optimization.