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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_modifications(self):
 """ Returns model modifications. """


        result = {}

        for key, value in self.__modified_data__.items():
            try:
                result[key] = value.export_data()
            except AttributeError:
                result[key] = value

        for key, value in self.__original_data__.items():
            if key in result.keys() or key in self.__deleted_fields__:
                continue
            try:
                if not value.is_modified():
                    continue
                modifications = value.export_modifications()
            except AttributeError:
                continue

            try:
                result.update({'{}.{}'.format(key, f): v for f, v in modifications.items()})
            except AttributeError:
                result[key] = modifications

        return result