python PEPs-KEY

https://www.python.org/dev/peps/

KEY 

    S - Standards Track PEP
    I - Informational PEP
    P - Process PEP

    A - Accepted proposal
    R - Rejected proposal
    W - Withdrawn proposal
    D - Deferred proposal
    F - Final proposal
    A - Active proposal
    D - Draft proposal
    S - Superseded proposal