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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def unpickle_dict(items):
    '''Returns a dict pickled with pickle_dict'''
    pickled_keys = items.pop('_pickled', '').split(',')
    ret = {}
    for key, val in items.items():
        if key in pickled_keys:
            ret[key] = pickle.loads(val)
        else:
            ret[key] = val
    return ret