code: def to_export(export):
          
          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!')
docs: Serializes export to id string
          :param export: object to serialize
          :return: string id