@classmethod
    def fromkeys(cls, iterable, value=None):
        d = cls()
        for key in iterable:
            d[key] = value
        return d
OD.fromkeys(S[, v]) -> New ordered dictionary with keys from S
dataset/ETHPy150Open baseblack/ReproWeb/3rdParty/python/ordereddict.py/OrderedDict.fromkeys