def to_export(export):
        """Serializes export to id string
        :param export: object to serialize
        :return: string id
        """
        from sevenbridges.models.storage_export import Export
        if not export:
            raise SbgError('Export is required!')
        elif isinstance(export, Export):
            return export.id
        elif isinstance(export, six.string_types):
            return export
        else:
            raise SbgError('Invalid export parameter!')