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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 export_modified_data(self):
 """ Retrieves the modified data in a jsoned form """


        def export_modfield(value, is_modified_seq=True):
            """
            Export modified item
            """
            try:
                return value.export_modified_data()
            except AttributeError:
                if is_modified_seq:
                    return value

        if self.__modified_data__ is not None:
            return [export_modfield(value) for value in self.__modified_data__]
        return list(x for x in [export_modfield(value) for value in self.__original_data__] if x is not None)