for majorkey, subdict in json_data.items():
    for one_majorkey in subdict:
        for subkey, value in one_majorkey.items():
            for each_subkey, valu_U in value.items():
                for each_sub_subkey, value_Q in valu_U.items():
                    for each_sub_sub_subkey, value_num in value_Q.items():
                        pass
python: читать словарь json и циклов