code: def downgrade():
      op.drop_table(SqlRegisteredModel.__tablename__)
      op.drop_table(SqlModelVersion.__tablename__)
  
file_path: mlflow/mlflow/store/db_migrations/versions/2b4d017a5e9b_add_model_registry_tables_to_db.py
imports: import time
  import logging
  from alembic import op
  import sqlalchemy
  from alembic import op
  from sqlalchemy import orm, func, distinct, and_
  from sqlalchemy import Column, String, ForeignKey, Float, Integer, BigInteger, PrimaryKeyConstraint, Boolean
  from mlflow.entities.model_registry.model_version_stages import STAGE_NONE
  from mlflow.entities.model_registry.model_version_status import ModelVersionStatus
  from mlflow.store.model_registry.dbmodels.models import SqlRegisteredModel, SqlModelVersion
label_desc: Use image node_id 2 for calling a global function with example usage: downgrade() without return types