omnihash.py

def omnihash(obj):
    """ recursively hash unhashable objects """
    if isinstance(obj, set):
        return hash(frozenset(omnihash(e) for e in obj))
    elif isinstance(obj, (tuple, list)):
        return hash(tuple(omnihash(e) for e in obj))
    elif isinstance(obj, dict):
        return hash(frozenset((k, omnihash(v)) for k, v in obj.items()))
    else:
        return hash(obj)