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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 _parse_json(s):
    ' parse str into JsonDict '

    def _obj_hook(pairs):
        ' convert json object to python object '
        o = JsonDict()
        for k, v in pairs.iteritems():
            o[str(k)] = v
        return o
    return json.loads(s, object_hook=_obj_hook)