@staticmethod
def _get_not_unwinded_fields_path(source_series, fields_not_to_unwind):
    """Form a list of lists with the path to the fields inside fields_not_to_unwind
        It is needed in order to use the json_normalize in pandas.io.json.

        Example: {"doctor": {"last_name": "Doe", "first_name": "John"}} will return
        -not_unwinded_fields_path = [["doctor", "first_name"],
                                    ["doctor", "last_name"]]
        """
    not_unwinded_fields_path = []
    not_unwinded_naming_map = {}
    for field in source_series:
        if field in fields_not_to_unwind:
            for subfield in source_series[field]:
                not_unwinded_fields_path.append([field, subfield])
    return not_unwinded_fields_path
