Py-EVM is a comprehensive Python implementation of the Ethereum protocol, supporting both the Proof-of-Work (PoW) and emerging Proof-of-Stake (PoS) specifications. Designed for versatility, it aims to serve as the definitive Python reference for Ethereum, offering easily modifiable, clear APIs, and solid documentation. Py-EVM provides foundational primitives essential for building diverse clients, accommodating both full and light use cases, and is highly adaptable to facilitate research and private chain applications. Quick installation and a robust development environment enable seamless engagement for developers, with guidelines for contributing to foster community collaboration and innovation.