code: def setup_classes(cls):
      Base = cls.DeclarativeBasic
  
      class Parent(Base):
          __tablename__ = "parent"
          __table_args__ = {"mysql_engine": "InnoDB"}
  
          id = Column(
              Integer, primary_key=True, test_needs_autoincrement=True
          )
  
      class Child(Base):
          __tablename__ = "child"
          __table_args__ = {"mysql_engine": "InnoDB"}
  
          id = Column(
              Integer, primary_key=True, test_needs_autoincrement=True
          )
          parent_id = Column(Integer, ForeignKey("parent.id"))
  
          parent = relationship(Parent, backref=backref("children"))
  
imports: from sqlalchemy import ForeignKey
  from sqlalchemy import Integer
  from sqlalchemy import String
  from sqlalchemy import testing
  from sqlalchemy.orm import backref
  from sqlalchemy.orm import declarative_base
  from sqlalchemy.orm import relationship
  from sqlalchemy.orm.attributes import instance_state
  from sqlalchemy.testing import AssertsExecutionResults
  from sqlalchemy.testing import expect_warnings
  from sqlalchemy.testing import fixtures
  from sqlalchemy.testing.fixtures import fixture_session
  from sqlalchemy.testing.schema import Column
label_desc: Use image node_id 1 for calling the LoadOnFKsTest obj's underlying member method code with example usage: obj.setup_classes(cls) without return types