I need a lightweight, browser-based tool built in Python that can talk to an automotive ECU over DoIP (ISO 13400). The core requirement is a working D-PDU API wrapper that exposes simple Send() and Receive() calls for UDS messages; once that foundation is stable I can extend it myself for data logging, parameter services, or fault diagnosis. Key points • Python stack preferred—Flask or FastAPI for the UI is fine as long as setup remains straightforward. • The code must establish a DoIP session, handle routing activation, and let me enter raw UDS hex or JSON-formatted payloads, then display responses in real time. • Keep the project self-contained: a requirements.txt or Poetry file, brief README, and any sample config needed to point at different ECUs or IPs. • Delivery is time-critical—I would like an initial functional prototype I can run locally as soon as possible, with clean, well-commented code so I can iterate from there.