code: def pickle_protocols():
      return iter([-1, 1, 2])
  
imports: from sqlalchemy import desc
  from sqlalchemy import ForeignKey
  from sqlalchemy import func
  from sqlalchemy import Integer
  from sqlalchemy import join
  from sqlalchemy import literal_column
  from sqlalchemy import MetaData
  from sqlalchemy import select
  from sqlalchemy import String
  from sqlalchemy import testing
  from sqlalchemy.ext import serializer
  from sqlalchemy.orm import aliased
  from sqlalchemy.orm import class_mapper
  from sqlalchemy.orm import column_property
  from sqlalchemy.orm import configure_mappers
  from sqlalchemy.orm import joinedload
  from sqlalchemy.orm import relationship
  from sqlalchemy.orm import scoped_session
  from sqlalchemy.orm import sessionmaker
  from sqlalchemy.testing import AssertsCompiledSQL
  from sqlalchemy.testing import eq_
  from sqlalchemy.testing import fixtures
  from sqlalchemy.testing.entities import ComparableEntity
  from sqlalchemy.testing.schema import Column
  from sqlalchemy.testing.schema import Table
label_desc: Use image node_id 1 for calling a global function with example usage: pickle_protocols() and returns: iter