code: def downgrade():
      # ### commands auto generated by Alembic - please adjust! ###
      op.drop_table("trial_values")
      op.drop_table("trial_user_attributes")
      op.drop_table("trial_system_attributes")
      op.drop_table("trial_params")
      op.drop_table("trials")
      op.drop_table("study_user_attributes")
      op.drop_table("study_system_attributes")
      op.drop_table("version_info")
      op.drop_index(op.f("ix_studies_study_name"), table_name="studies")
      op.drop_table("studies")
  
label_desc: Use image node_id 2 for calling a global function with example usage: downgrade() without return types