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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_deleted_fields(self):
 """ Returns a list with any deleted fields form original data. In tree models, deleted fields on children will be appended. """

        result = []
        if self.__modified_data__ is not None:
            return result

        for index, item in enumerate(self):
            try:
                deleted_fields = item.export_deleted_fields()
                result.extend(['{}.{}'.format(index, key) for key in deleted_fields])
            except AttributeError:
                pass
        return result