def dedup(it):
    for _, group in groupby(it):
        for lab in group:
            yield lab
            break
Supplies a list of backends for future use.
dataset/ETHPy150Open dossier/dossier.web/dossier/web/label_folders.py/dedup--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/tools/dev_appserver_multiprocess.py/DevProcess.Init