Python - Unflatten dict

def unflatten(dictionary):
    resultDict = dict()
    for key, value in dictionary.items():
        parts = key.split(".")
        d = resultDict
        for part in parts[:-1]:
            if part not in d:
                d[part] = dict()
            d = d[part]
        d[parts[-1]] = value
    return resultDict

from collections import defaultdict
def unflatten(d):
    ret = defaultdict(dict)
    for k,v in d.items():
        k1,delim,k2 = k.partition('.')
        if delim:
            ret[k1].update({k2:v})
        else:
            ret[k1] = v
    return ret