flatten a nested dict

gistfile1.py

def dict_flatten(d, delim='.', prefix=[]):
    def pairs(d, prefix):
        def flatten(k, v):
            if isinstance(v, dict):
                return pairs(v, k)
            else:
                return [(k, v)]
        for k, v in d.iteritems():
            for e in flatten(prefix + [k], v):
                yield e
    return dict((delim.join(k), v) for k, v in pairs(d, prefix))