@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 xraypy/xraylarch/doc/sphinx/ext/backports.py/OrderedDict.fromkeys